Steering gear| combined with hydraulic booster. Working pairs: a screw with a nut on circulating balls and a piston-rack that engages with the toothed sector of the bipod shaft |
| Steering gear ratio |
20
|
| Drive from the steering column shaft with steering wheel to the steering mechanism |
via cardan shaft and angular transmission |
| Angular gear ratio |
1
|
| Power steering pump |
vane, double acting, left rotation |
| Power steering pump drive |
gear, from the engine crankshaft |
| Pump drive ratio |
1,25
|
Steering Column
(Fig. 272) is attached in the upper part to a bracket installed on the interior panel of the cabin, in the lower part - to a flange on the cabin floor. The column is connected to the steering mechanism by a cardan shaft.
Shaft 1 of the column rotates in two ball bearings 4. The axial clearance in the bearings is adjusted with a nut 8. The lubricant in the bearings is replaced only when disassembling the column.
Rice. 272. Steering column: 1 - column shaft; 2 - retaining ring; 3 - expansion ring; 4 - ball bearing; 5 - column pipe; 6 - holder with seal; 7 - lock washer; 8 - bearing adjustment nut
Cardan shaft
(Fig. 273) with two hinges on needle bearings 4, into which grease 158 is added during assembly. The bearings do not need to be replenished with grease during operation.
Rubber rings 5 are used to prevent dirt and moisture from entering the hinge joint.
Rice. 273. Steering cardan shaft: 1 - fork; 2, 9 - thrust rings; 3 - cross; 4 - needle bearing; 5.8 - sealing rings; 6 - fork with splined rod; 7-ring sealing ring; 10 - fork with splined bushing
The sliding spline connection of the propeller shaft makes it possible to change the distance between the hinges when the cab is tipped and serves to compensate for inaccuracies in the installation of the cab with the steering column relative to the frame with the steering mechanism, as well as their mutual movements.
Before assembly, 28...32 g of lubricant 158 is placed in the bushing, the splines are coated with a thin layer.
To retain the lubricant and protect the connection from contamination, a rubber seal with a thrust ring 9 is used, pressed by a holder 7.
The propeller shaft forks are attached to the column shaft and the drive gear shaft of the angular gearbox with wedges, which are tightened with nuts and cotter pins.
Angular gearbox
(Fig. 274) with two bevel gears with a spiral tooth transmits rotation from the propeller shaft to the steering screw. The drive gear of the angular reducer is made integral with shaft 1 and is installed in housing 4 on ball bearings 5.
The ball bearings are pressed onto the gear shaft and are held from axial movement by nut 16. To prevent spontaneous loosening, the nut flange is pressed into the groove on the gear shaft.
The driven gear 11 rotates in two ball bearings 7, 10, mounted on the gear shank with interference. The driven gear is kept from longitudinal displacements by a retaining ring 9 and a thrust cover 12.
The engagement of the bevel gears is regulated by spacers 6 installed between the housings of the drive gear and the bevel gear.
Rice. 274. Angular gearbox: 1 - drive gear shaft; 2 - cuff; 3 - housing cover; 4 - drive gear housing; 5, 7, 10 - ball bearings; 6 - adjusting gaskets; 8, 15, 19 - sealing rings; 9 - retaining ring; 11 - driven gear; 12 - thrust cover; 13 - gear housing; 14 - spacer sleeve; 16 - bearing fastening nut; 17 - washer; 18 - thrust ring; 20 - protective cover
In the angular gearbox drive gear shaft-propeller shaft fork assembly, instead of a wedge joint, a splined connection is used with fastening with a bolt and nut without a cotter pin.
The steering bipod is attached to the bipod shaft using conical splines, tightened with a nut and a lock washer.
Steering mechanism with built-in hydraulic booster
(Fig. 275) is attached to the front bracket of the front left spring. The bracket is fixed to the car frame.
Carter 14 of the steering mechanism, in which the piston-rack moves, also serves as the working cylinder of the hydraulic booster.
Steering gear screw 17 has a ground helical groove. The same groove is ground in nut 18 and two holes are drilled into it. The holes are connected by an oblique groove milled on the outer surface of the nut.
Two identical grooves 19 of semicircular cross-section, installed in the mentioned holes, and a groove form a bypass channel through which the balls 20, rolling out of the screw channel formed by the threads of the screw and nut, again enter it.
Rice. 275. Steering mechanism with built-in hydraulic booster: 1 - front cover; 2 - power steering control valve; 3, 29 - retaining rings; 4 - floating bushing; 5, 7 - sealing rings; 6, 8 - spacer rings; 9 - set screw; 10 - bipod shaft; 11 - bypass valve; 12 - protective cap; 13 - rear cover; 14 - steering gear housing; 15 - piston-rack; 16 - magnetic drain plug; 17 - screw; 18 - ball nut; 19 - gutter; 20 - ball; 21 - angular gearbox; 22 - thrust bearing; 23 - spring washer; 24 - nut; 25 - thrust washer; 26 - adjusting washer; 27 - adjusting screw; 28 - lock nut of the adjusting screw; 30 - side cover
To prevent the balls from falling out of the screw channel, a tongue is provided in each groove that fits into the screw groove of the screw and changes the direction of movement of the balls. The number of circulating balls in a closed screw channel is thirty-one, eight of which are in the bypass channel. The helical groove on the screw in its middle zone is designed so that a slight interference is formed between the screw, nut and balls. This is necessary to ensure gap-free mating of parts in this area.
When moving the nut, due to the fact that the depth of the groove on the screw from the middle to the ends increases slightly, a small gap appears in the mating of the screw and the nut. This clearance is necessary to ensure greater durability of the middle part of the propeller, as well as to facilitate the return of the steered wheels to the center position after turning and better stabilize the movement of the vehicle.
In addition, loosening the seat of the ball nut on the screw to the edges of its screw groove makes it easier to select balls and assemble the ball screw pair.
Since the transfer of axial force from the screw to the nut is carried out by means of balls, friction losses in the screw pair are minimal.
After assembling the nut with the screw and balls, it is installed in the piston-rack 15 and fixed with two setscrews 9, which are cored into the annular groove made on the piston-rack.
The piston-rack engages with the toothed sector of the bipod shaft 10. The bipod shaft rotates in a bronze bushing pressed into the steering gear housing and into the aluminum side cover 30.
The thickness of the teeth of the bipod shaft sector and the piston-rack is variable along the length, which allows you to change the engagement gap by moving the adjusting screw 27 screwed into the side cover. The head of the adjusting screw, on which the thrust washer 25 rests, fits into the socket of the bipod shaft. The axial movement of the adjusting screw in the bipod shaft, maintained at 0.02 ... 0.08 mm during assembly, is ensured by selecting an adjusting washer 26 of the appropriate thickness.
Parts 27, 26, 25 are held in the seat of the bipod shaft by a retaining ring 29. The middle cavity between the teeth of the rack, which engages with the middle tooth of the toothed sector of the bipod shaft, is made slightly smaller in width than the rest. This is necessary in order to avoid jamming of the worn mechanism after its adjustment when turning the bipod shaft.
On the part of the steering gear screw located in the cavity of the angular gearbox housing, splines are cut with which the screw mates with the driven gear of the angular transmission.
Power steering control valve
(Fig. 276) is attached to the bevel gear housing with a bolt and four studs (or five studs - one long and four short). The valve body 8 has a central hole made with great precision and six (three through and three blind) smaller holes located around it.
Rice. 276. Power steering control valve: 1 - blind hole plunger; 2, 5 - springs; 3 - threaded plug; 4 - check valve; 6 - spool; 7 - reactive plunger; 8 - valve body; 9 - sealing ring; 10 - safety valve
The control valve spool 6, located in the central hole, and the thrust bearings 22 (see Fig. 275) are secured to the screw with a nut 24, the collar of which is pressed into the groove of the screw 17. A conical spring washer 23 is placed under the nut, making it possible to regulate the tightening force of the thrust bearings . The concave side of the washer is directed towards the bearing. The large bearing rings face the spool.
The steering mechanism screw and the spool rigidly connected to them can move in each direction from the average position by 1...1.2 mm. The amount of movement is determined by the depth of the recesses at the ends of the valve body and is limited by large bearing rings that abut the ends of the mentioned recesses.
Two reaction plungers 7 are inserted into each of the three through holes of the valve body (see Fig. 276) with centering springs between them.
To ensure the same reactive force on the steering wheel from oil pressure and the necessary equal active areas of the plungers when turning both right and left, plunger 1 is installed in each of the three blind holes facing the bevel gear. The total area of these three reactive elements are equal in size to the cross-sectional area of the screw at the point of its seal in the thrust cover of the bevel gear.
One of the plungers, located in the blind holes, has a ball check valve 4 built in, which connects the high and low pressure lines in the event of a failure of the steering hydraulic system and thus ensures the ability to drive the vehicle. In this case, the steering operates like a conventional mechanical system without power assistance.
A safety valve 10 is also installed in the control valve housing, connecting the discharge and drain lines at a pressure in the system exceeding 7357.5 ... 7848 kPa (75 ... 80 kgf/cm 2), and thus protecting the pump from overheating , and the mechanism parts from excessive loads.
The safety valve is located in a separate boss, which makes it possible to check, adjust or replace its parts if necessary.
The cavities located under the front cover 1 (see Fig. 275) and in the bevel gear are connected by holes in the control valve body to the drain line and sealed at the ends with rubber O-rings. Similar rings seal all the fixed connections of the steering mechanism and power steering parts.
The bipod shaft is sealed with a cuff with a special thrust ring that prevents the working edge of the cuff from turning out under high pressure. The outer cuff protects the bipod shaft from dust and dirt. The piston in the cylinder and the steering gear screw in the bevel gear housing cover are sealed with fluoroplastic rings 5 and 7 in combination with rubber spacer rings 6, 8. The bipod shaft adjusting screw is sealed with a rubber ring.
The shaft seal of the drive gear of the angular gearbox is combined and consists of two cuffs, which are fixed with a split thrust ring.
In the steering gear housing there is a drain plug 16 with a magnet, which serves to catch steel and cast iron particles, and a bypass valve 11, which is used when filling and bleeding the steering hydraulic system.
High and low pressure hoses and pipelines are connected from the pump to the control valve body. The former directs the oil to the mechanism, and the latter returns it to the hydraulic system reservoir.
The power steering operates as follows. When moving in a straight line, screw 15 (Fig. 277) and spool 20 are in the middle position. The injection lines 26 and drain 32, as well as both cavities 7 and 25 of the hydraulic cylinder are connected. Oil passes freely from pump 4 through control valve 19 and returns to reservoir 31 of the hydraulic system. When the driver turns the steering wheel 1, screw 15 rotates. Due to the resistance to rotation of the wheels, which initially holds the wheels 12 and the piston-rack 8 in place, a force arises that tends to move the screw in the axial direction in the corresponding direction. When this force exceeds the pre-compression force of the centering springs 23, the screw moves and displaces the spool rigidly connected to it. In this case, one cavity of the power steering cylinder communicates with the discharge line and is disconnected from the drain line, the other, on the contrary, remaining connected to the drain, is disconnected from the discharge line. The working fluid supplied from the pump to the corresponding cavity of the cylinder exerts pressure on the piston-rack 8 and, creating additional force on the sector of the shaft 6 of the steering bipod, contributes to the rotation of the steered wheels. The pressure in the working cavity of the cylinder is set proportional to the amount of resistance to wheel rotation. At the same time, the pressure in the cavities under the reaction plungers 22 increases. The greater the resistance to rotation of the wheels, and therefore the higher the pressure in the working cavity of the cylinder, the greater the force with which the spool tends to return to the middle position, as well as the force on the steering wheel. This gives the driver a “feeling of the road.”
Rice. 277. Diagram of operation of the power steering: 1 - steering wheel; 2 - hydraulic system filter safety valve spring; 3 - filter; 4 - power steering pump; 5 - bypass valve; 6 - bipod shaft with gear sector; 7 - rear cavity of the hydraulic booster; 8 - piston-rack; 9 - bipod; 10 - longitudinal thrust; 11 - transverse thrust; 12 - front wheel of the car; 13 - magnetic plug; 14 - ball nut; 15 - screw; 16 - steering gear housing; 17 - check valve; 18 - safety valve of the steering mechanism; 19 - power steering control valve; 20 - spool; 21 - thrust bearing; 22 - reactive plunger; 23 - centering spring; 24 - angular gearbox; 25 - front cavity of the hydraulic booster; 26 - discharge line; 27 - cardan shaft; 28 - radiator; 29 - steering column; 30 - filling filter; 31 - pump reservoir (hydraulic booster); 32 - drain line; 33 - bypass valve spring; 34 - safety valve of the pump; 35 - bypass valve; A and B - throttling holes; I - movement straight or neutral; II - turn right; III - turn left
When the steering wheel stops turning, if it is held by the driver in the turned position, the spool, under the action of centering springs and increasing pressure in the reaction cavities, moves to the middle position. In this case, the spool does not reach the middle position. The size of the gap for the passage of oil into the return line will be set so that in the pressurized cavity of the cylinder, the pressure necessary to hold the steered wheels in the rotated position is maintained.
If the front wheel begins to turn sharply while the car is moving in a straight line, for example due to hitting some obstacle on the road, the bipod shaft, turning, will move the piston-rack. Since the screw cannot rotate (the driver holds the steering wheel in one position), it will also move axially along with the spool. In this case, the cylinder cavity, into which the piston-rack moves, will be connected to the pump discharge line and separated from the return line. The pressure in this cylinder cavity will begin to increase, and the blow will be balanced (softened) by the increasing pressure.
The screw, nut, balls, thrust bearings, as well as the angular gear, propeller shaft and steering column are loaded with relatively small forces during power steering operation. At the same time, the gearing of the steering mechanism, the bipod shaft and the crankcase perceive the main force created by the oil pressure on the piston-rack.
Warning.
When the hydraulic booster is not working, the steering mechanism still ensures that the wheels turn, but the ball screw and other parts are already subject to full loads. Therefore, during prolonged operation with the hydraulic system not working, premature wear appears and breakdowns of the mentioned parts may occur. Driving with the power steering inoperative, including towing the vehicle, should be kept to a minimum.
Power steering pump with oil reservoir
(Fig. 278) is installed in the camber of the cylinder block and is driven by the engine crankshaft. Gear 1 is fixed on shaft 5 of the pump with a key 6 and secured with a nut 2 with a cotter pin 3.
Rice. 278. Power steering pump: 1 - drive gear; 2 - gear fastening nut; 3 - cotter pin; 4, 15 - washers; 5 - pump shaft; 6 - segmental key; 7, 10 - thrust rings; 8 - ball bearing; 9 - oil scraper ring; 11 - cuff: 12 - needle bearing; 13 - filler cap; 14 - filler filter; 16 - bolt; 17, 36, 39 - sealing rings; 18 - filter pipe; 19 - safety valve; 20 - tank cover with a spring; 21, 27, 28 - sealing gaskets; 22 - pump reservoir; 23 - filter; 24 - collector; 25 - tank tube; 26 - fitting; 29 - pump cover; 30 - bypass valve spring; 31 - safety valve seat; 32 - adjusting gaskets; 33 - combination valve; 34 - distribution disk; 35 - pump plate; 37- stator; 38 - rotor; 40 - pump housing; A and B - throttling holes
The pump is a vane type, double acting, that is, in one revolution of the shaft two complete suction cycles and two discharge cycles are completed.
The pump rotor 88, which is located inside the stator 37 and is driven by the splined end of the pump shaft, has ten slots in which the plates 85 move.
The stator, on one side, is pressed against the precisely machined end of the pump housing 40; on the other hand, the distribution disk 84 is adjacent to the stator. The position of the stator relative to the housing and the distribution disk is fixed with pins. An arrow on the outer surface of the stator indicates the direction of rotation of the pump shaft.
When the pump shaft rotates, the plates are pressed against the curved surface of the stator under the action of centrifugal force and oil pressure entering the space under them from the cavity of the pump cover through channels in the distribution disk.
Chambers of variable volume are formed between the outer surface of the rotor, the plates and the inner surface of the stator. The volume of these chambers increases as they pass through the suction zones and they are filled with oil. To fill the chambers more completely, oil is supplied both from the side of the pump housing through two windows, and from the side of the recesses in the distribution disk through six holes made in the stator and located in threes opposite the suction windows. When passing through the injection zones, the volume between the plates decreases, the oil is forced out through the channels in the distribution disk into the cavity of the pump cover, which communicates through a calibrated hole A with the discharge line. In areas of the stator surface with a constant radius (between the suction and discharge zones), the volume of the chambers does not change. These areas are necessary to ensure minimal leakage of the working fluid (oil flow between zones).
To avoid “locking” the oil, which would prevent the movement of the plates, the space under them is connected through additional small channels in the distribution disk with a cavity in the pump cover 29. The pump shaft rotates in the housing on 12 needle and 8 ball bearings, which in the adopted design of the pump pump assembly are unloaded from radial forces.
The pump is equipped with a combination valve 33 located in the pump cover, which combines a safety valve and a bypass valve. The first in this case is an additional (backup) safety valve in the hydraulic system. Adjustable to pressure 8336... 8826 kPa (85... 90 kgf/cm2). The second limits the amount of oil entering the system.
The bypass valve operates as follows. At minimum engine speed, the valve is pressed by spring 30 (see Fig. 209) to the distribution disc. Oil from the cavity in the pump cover through calibrated hole A enters the discharge line. The cavity under the valve, where the spring 30 is located, communicates with the discharge line through a small diameter hole.
With an increase in the rotation speed of the engine crankshaft, and therefore the pump flow, due to the resistance of hole A, a pressure difference is formed in the cavity of the cover (in front of the valve) and the pump discharge channel (behind the valve). The greater the amount of oil passing per unit time through this hole, the greater the pressure drop, and does not depend on the pressure value.
Excess pressure in the cover cavity, acting on the left end of the bypass valve, overcomes the resistance of the spring. At a certain pressure difference, the force tending to move the valve increases so much that the spring is compressed, and the valve, moving to the right, opens the exit of some of the oil from the cavity of the lid into the tank. The more oil the pump supplies, the more of it is bypassed through the valve back into the reservoir. Thus, there is almost no increase in the oil supply to the system above a given limit.
The operation of the bypass valve when the safety valve built into it is triggered is carried out in a similar way.
When the ball valve opens, it allows a small flow of oil into the reservoir through the radial holes in the bypass valve. In this case, the pressure on the right end of the bypass valve drops, since the flow of oil through the ball valve is limited by hole B. In this case, the valve, moving to the right, opens the outlet for most of the bypassed oil into the tank.
The safety valve should be adjusted only using adjusting washers 32 placed under the valve seat 31.
To prevent noise and reduce wear of pump parts when the engine speed increases, a manifold 24 is provided, which forcibly directs the oil drained by the bypass valve into the internal cavity of the pump housing, thus providing excess pressure in the suction zones. This is necessary to avoid the formation of excessive vacuum and, as a consequence, the appearance of cavitation.
A specially selected variable cross-section of the internal cavity of the manifold before and after the holes in it ensures that the flow of oil in the manifold simultaneously captures the required amount of oil from the hydraulic system reservoir.
The hydraulic system reservoir 22, stamped from sheet steel, is attached directly to the pump body and cover using four bolts through intermediate rubber gaskets 28. The reservoir contains a collapsible strainer 23, which is a package of individual filter elements, which, if significantly clogged, is pressed upward by increased pressure. In this case, the oil directly enters the tank. In addition, the tank has a fill filter 14 and a safety valve 19, which prevents the pressure in the tank cavity above the oil from increasing by more than 19.6... 29.4 kPa (0.2... 0.3 kgf/cm2).
For modernized cars.
The filter, located in the power steering pump reservoir, is made in the form of a non-separable structure, consisting of a paper curtain placed between two metal shells, which are glued to the upper and lower filter covers (see Fig. 279).
Rice. 279. Power steering pump filter
The tank cover 20 is sealed with rubber gaskets 21 and a ring 17. The sealing of the end surfaces of the housing and the cover with the stator is ensured by rubber rings 36 and 39 of circular cross-section.
Power steering system pipes.
For pipelines in the hydraulic booster system, seamless steel pipes and braided rubber hoses are used. High-pressure hoses have two internal combined braids consisting of cotton and lavsan threads. The ends of the sleeve are embedded in special tips, which are crimped during assembly.
Low pressure hoses have one internal thread (lavsan) braid and are attached to the hydraulic system pipelines using clamps.
The pipes are connected to each other and fastened to the pump and the power steering control valve using union nuts and fittings with external threads. The sealing of pipelines is ensured by the fact that the ends of the pipes, made with double flaring, are pressed against the conical surfaces of the corresponding parts. The tightening torque of nuts in pipeline connections must be within 78.5... 98.1 Nm (8... 10 kgcm).
Radiator 4
(see Fig. 270) is designed to cool the oil in the power steering system and is an aluminum finned tube installed in front of the engine cooling radiator. Oil is supplied from the steering mechanism to the radiator and from the radiator to the pump through rubber hoses.
The steering drive includes longitudinal and transverse steering rods.
The longitudinal link (Fig. 280) connects the bipod of the steering mechanism with the upper arm of the left steering knuckle and is a solid forged part with non-adjustable hinges, including a ball pin 1, upper 4 and lower 5 liners, a spring and a threaded cover 8 with a lock washer 7.
Rice. 280. Longitudinal steering rod: 1 - ball pin; 2 - lining clip; 3 - protective cover; 4 - upper liner; 5 - lower liner; 6 - pressure spring; 7 - cover washer; 8 - cover; 9 - oiler; 10 - protective cover
The transverse linkage of the steering linkage (Fig. 281), which is part of the technological assembly unit “front axle assembly,” is tubular with threaded ends onto which ends 2 with ball joints are screwed.
By changing the position of the tips on the rod, you can adjust the toe-in of the steered wheels. Each tip is fixed with two bolts 3. The lateral link joints are also non-adjustable, consisting of a ball pin 11, upper 12 and lower 13 liners, a spring 7 and a cover 6, attached with a sealing paronite gasket 4 to the end of the rod with bolts 8.
The hinges are lubricated through oil nipples 5. Rubber pads are used to protect the hinges from dust and dirt getting into them.
Rice. 281. Tie rod: 1 - transverse rod; 2 - tip; 3 - tip fastening bolt; 4 - sealing gasket; 5 - oiler; 6 - cover; 7- spring; 8 - cover fastening bolt; 9 - protective cover; 10 - lining clip; 11 - ball pin; 12 - upper liner; 13 - lower liner
Maintenance
For daily maintenance
Check the condition of the steering drive (without using special tools).
At service 1:
Check the oil level in the power steering pump reservoir, if necessary, add oil to the specified level;
Lubricate the steering linkage joints through the grease nipples until fresh grease appears in the gaps.
Check the oil level in the pump reservoir with a pointer mounted in the filler plug of the reservoir, with the front wheels set straight. Before removing the plug, thoroughly wipe it and the filler neck of the tank with a rag moistened with diesel fuel or kerosene.
The oil level should be between the marks on the gauge. If necessary, add oil to the specified level with the engine running at minimum crankshaft speed. Fill the oil through a funnel with a double mesh and a filler filter installed in the neck of the tank.
At service 2:
Check the clearances in the steering rod joints and driveshaft;
Check and, if necessary, restore the free play of the steering wheel within acceptable limits;
Remove and wash the pump filter.
For modernized cars
During maintenance (service 2) provision is made for replacing the pump filter if it is significantly clogged.
Check the free play of the steering wheel with the car equipped (without load) with the engine running at an engine speed of 600... 1200 min -1. The tire pressure should be normal and the front wheels should be straight. The free play of the steering wheel on a new car should not exceed 15°. The maximum permissible free play is 25°.
Measure the free play with the K-402 or K-187 device, turning the steering wheel to the right and left until the left front wheel begins to turn. Count the angle on the angular scale of the device from the conventional zero, which is set in the middle of the range of free swing of the steering wheel.
If the free play of the steering wheel is more than permissible, check the presence of air in the power steering hydraulic system, the condition of the steering rod joints, the fastening and adjustment of the steering mechanism, the clearances in the joints of the steering driveshaft, the tightening of the driveshaft mounting wedges, and the adjustment of the steering wheel hub bearings. If the tightening or adjustments are incorrect, restore them. If it is impossible to eliminate the gaps in the joints or splines of the steering propeller shaft, replace the shaft.
Wash filler filter 14 (see Fig. 278) and filter element with gasoline. If the filter elements are significantly clogged with resinous deposits, additionally rinse them with solvent 646 GOST 18188-72.
To change the oil and bleed the power steering system:
1. Disconnect the trailing link from the steering arm or raise the front axle so that the steered wheels do not touch the ground. Remove the power steering pump reservoir cap.
Do not fill or bleed the steering hydraulic system with the tie rod connected or the wheels not raised.
2. Turn the steering wheel to the left all the way and open the drain hole by unscrewing the magnetic plug from the steering gear housing. Drain the oil until it completely flows out of the hole.
3. Wash the pump, pipelines and hydraulic booster, to do this:
Unscrew the filter from the pump reservoir manifold and remove the remaining contaminated oil from the power steering pump reservoir;
Wash the parts of the disassembled filter and the drain plug of the steering mechanism, clearing them of dirt. After cleaning and rinsing, assemble the pump filter and screw it into place;
Pour 2 liters of clean oil into the pump reservoir through a funnel with a double mesh and drain through the drain hole in the steering gear housing, turning the steering wheel from lock to lock.
4. Fill with fresh oil and remove air from the system in the following order:
Screw the magnetic plug into the drain hole of the steering gear housing;
Remove the rubber cap from the bypass valve of the steering mechanism and put a transparent elastic hose on its spherical head, the open end of which is lowered into a glass container with a capacity of at least 0.5 liters. The vessel must be filled with oil to half its volume;
Unscrew the steering gear bypass valve 1/2... 3/4 turn;
Install the pump reservoir cap;
Turn the steering wheel to the left until the centering springs begin to compress (determined by increasing force on the steering wheel; do not turn the wheel all the way);
Remove the filler plug from the pump reservoir cap and from a container with a capacity of at least 1.5 liters, pour oil into the pump reservoir until its level stops decreasing;
Start the engine and, while operating at minimum speed, add oil to the pump reservoir, not allowing its level to drop, until the release of air bubbles from the hose placed on the bypass valve stops;
Close the bypass valve;
Turn the steering wheel to the right until the centering springs begin to compress (determined by increasing force on the steering wheel) and return it to the left position again. Keeping the steering wheel in the left position, unscrew the bypass valve 1/2... 3/4 turn and again watch for the release of air bubbles. After the bubbles stop, close the bypass valve;
Repeat the previous operation at least two times, as a result, clean (without air) oil should come out of the bypass valve. If the release of air bubbles from the hose continues, repeat the operation one or two more times; At the same time, monitor the oil level in the pump reservoir, maintaining it between the marks on the level indicator;
Stop the engine;
Remove the hose from the spherical head of the bypass valve and place the protective cap on it;
Check the oil level in the pump reservoir and, if necessary, add it. Install the filler cap of the tank;
Connect the longitudinal steering rod to the bipod of the steering mechanism.
When refueling the hydraulic system, keep in mind that poor-quality oil pumping, which leaves air in the hydraulic system, is a common cause of the “heavy steering wheel” defect (increased force on the steering wheel), as well as a decrease in steering sensitivity and poor road holding by the car.
Repair
When starting to repair the steering mechanism, power steering pump and other steering assembly units, keep in mind that the restoration of parts that have exhausted their functionality due to wear in these assembly units is unacceptable. The production of such parts with high precision and cleanliness of working surfaces, as well as their selective selection during assembly, is possible only in specialized production conditions. Repair of steering mechanisms and pumps in the conditions of motor transport enterprises is only possible by replacing failed units or parts with serviceable ones.
Check and adjust the steering mechanism on the vehicle with the tie rod disconnected and the engine not running.
First check the wheel balancing, air pressure in the tires, the presence of lubrication in the steering and wheel hubs, the adjustment of the wheel hub bearings and steering rods, the operation of shock absorbers, and the installation of the front wheels. In addition, check the oil level in the power steering pump reservoir, make sure there is no air in the system, sediment or dirt in the reservoir and on the pump filter, and oil leaks in the oil pipe connections.
Measure the force on the steering wheel with a spring dynamometer attached to the wheel rim in the following positions:
1. The steering wheel is turned more than two turns from the center position. The force on the steering wheel should be 5.9... 15.7 N (0.6... 1.6 kgf). In this case, the gearing and the ball screw pair are brought to a position close to the extreme, where friction in these units is practically eliminated, and the magnitude of the force is determined primarily by the friction moment in the thrust bearings, seals and bushings of the steering mechanism.
A discrepancy between the force on the steering wheel rim and the specified value indicates improper (insufficient or excessive) tightening of the propeller thrust bearings, or means that parts of the ball nut assembly are damaged.
Insufficient tightening of the thrust bearings leads to a violation of the car's directional stability (the car does not hold the road well); excessive, along with damage to the parts of the ball nut assembly, leads to jamming of the steering mechanism (the phenomenon of “residual pressure”).
2. The steering wheel is turned 3/4 of a turn from the center position. The force should not exceed 19.6... 22.6 N (2... 2.3 kgf). In this position, friction is added to the ball screw due to the preload of the balls. Deviation of the magnitude of the force on the steering wheel rim from the specified values is caused by damage to the parts of the ball screw assembly.
3. The steering wheel goes to the middle position. The force on the steering wheel should be 3.9... 5.9 N (0.4... 0.6 kgf) greater than the force obtained when measuring in the second position, but not exceed 21.8 N (2.2 kgf).
In this case, the adjustment of the steering gear gear is checked. If the force is less than the specified value, the gap in the gearing is greater than permissible, and the car will not hold the road well. If the force is greater, the engagement is too “tight”, which may be, along with other factors, the reason for poor self-return of the steered wheels to the middle position.
If, when measuring the forces in the positions listed above, it turns out that they do not correspond to the specified values, adjust the steering mechanism. If necessary, remove the mechanism from the vehicle to perform partial or complete disassembly and additional inspection.
Start adjusting the steering mechanism by measuring the force in the third position. At the same time, use the adjusting screw of the bipod shaft to bring the force to normal. When rotating the screw clockwise, the force will increase, and when rotating counterclockwise, it will decrease.
To regulate the force in the first position, it is necessary to partially disassemble the steering mechanism in order to tighten or loosen the nut securing the thrust bearings. To eliminate the causes of the force discrepancy in the second position, complete disassembly of the steering mechanism is required. Complete disassembly may only be carried out at a company that repairs steering mechanisms or in specialized workshops. The procedure for removing, disassembling and assembling the steering mechanism, as well as its subsequent testing and installation on the car is outlined below.
When checking the pressure in the hydraulic steering system of a car
In the pressure line between the pump and the steering mechanism, install a device (Fig. 282) that has a pressure gauge 2 with a scale of up to 9810 kPa (100 kgf/cm2) and valve 1, which stops the oil supply to the hydraulic booster.
Rice. 282. Scheme for checking pressure in the hydraulic steering system: 1 - valve; 2 - pressure gauge; 3 - high pressure line; 4 - pump; 5 - low pressure line; 6 - steering mechanism
When checking the pressure, open the valve and turn the steering wheel all the way, applying a force of at least 98.1 N (10 kgf) to the steering wheel. The oil pressure at a crankshaft rotation speed of 600 rpm must be at least 7355 kPa (75 kgf/cm2).
If the oil pressure is less than 7355 kPa (75 kgf/cm2), then slowly close the valve, monitoring the increase in pressure on the pressure gauge. When the pump is working properly, the pressure should rise and be at least 8336 kPa (85 kgf/cm2). In this case, the fault must be looked for in the steering mechanism (incorrect adjustment of the safety valve or excessive internal leaks). If the pressure does not increase, the pump is faulty. If the pressure with the valve closed is greater than the pressure that was with the valve open, but below 7355 kPa (75 kgf/cm2), then both units may be faulty.
To check the correct operation of the power steering control valve, disconnect the longitudinal steering rod, open the valve and turn the steering wheel all the way using a force of at least 98.1 N (10 kgf) at a crankshaft speed of 1000 rpm.
When the force on the steering wheel ceases, the pressure should drop to 294... 490 kPa (3... 5 kgf/cm2). Carry out this check in two extreme positions. If the pressure does not decrease, this indicates that the valve spool or reaction plungers are stuck.
When checking, do not keep the valve closed and the wheels turned all the way for more than 15 seconds. Carry out the check at an oil temperature in the tank of 65... 75°C. If necessary, the oil can be heated by turning the wheel all the way in both directions and holding them in extreme positions for no more than 15 seconds.
Adjusting bearing tightening
steering column shaft
carry out if axial movement of the shaft is felt, and the torque of the shaft is less than 29.4... 78.5 N cm (3... 8 kgf cm) [which corresponds to a force of 1.15... 3.08 N ( 0.118...0.314 kgf) applied on a steering wheel radius of 255 mm] with the driveshaft disconnected.
Adjust the tightening of the bearings by rotating the adjusting nut 8 (see Fig. 272), having first straightened the lock washer 7. When adjusting, tightening the nut, turn shaft 1 by the steering wheel in both directions so as not to overtighten the nut.
It is unacceptable to tighten the nut and then unscrew it to obtain the specified torque of the steering column shaft, since this may damage the steering column shaft bearing rings stamped from sheet steel. After completing the adjustment, bend one of the lock washer's antennae back into the groove of the nut. If for some reason the steering column was disassembled, then apply fresh grease to the shaft bearings during reassembly.
When assembling the propeller shaft
Make sure that the axes of the holes in the forks for the mounting wedges are in parallel planes and are located as shown in Fig. 273. Install the propeller shaft on the vehicle so that the fork with the splined sleeve faces upward. At the same time, the lubricant embedded in the cavity of the bushing ensures better lubrication of the splines.
Replacing the tie rod
perform in the following order:
- hang up the front axle of the car;
Unscrew and unscrew the nut securing the ball pin of the left rod end with the corresponding lower steering knuckle arm;
- knocking the ball pin out of the conical hole of the lever, disconnect the left end of the steering linkage rod;
- perform the same operations with the right tie rod end and remove the tie rod from the car;
Install the ends of the ball pins of the new tie rod ends in the holes of the lower arms, tighten and cotter the fastening nuts. The tightening torque of the tie rod ball pin nuts is 245...314 Nm (25...32 kgfm). Install the transverse link so that the ball pin grease fittings on the link ends face rearwards in the direction of the vehicle;
- lower the front axle.
To replace the longitudinal steering rod:
- lift the front axle of the car and turn the steered wheels to the left as far as possible;
Undo the cotter pin and unscrew the nut securing the ball pin of the longitudinal steering rod on the side of the steering bipod;
- knocking the ball pin out of the conical hole of the bipod, disconnect the rod;
Perform the same operations with the other longitudinal link joint at the point where it connects to the upper arm of the left steering knuckle and remove the link from the vehicle.
Install the new longitudinal rod in the reverse order of removal, paying attention to the correct connection and the correspondence of the different rod heads to the installation locations. Lower the front axle of the vehicle. Tighten the nuts securing the ball pins of the longitudinal steering rod with a torque of 245... 314 N·m (25... 32 kgf·m).
To remove the steering wheel
, if it cannot be removed by lightly tapping it with a hammer from bottom to top, use a puller. Having first removed the decorative cover and unscrewed the steering wheel fastening nut, insert the grip hooks 2 (Fig. 283) into the holes of the steering wheel hub and turn clockwise until it stops. Pressing tip 3 against the end of the shaft, screw screw 1 into the grip until the steering wheel is completely removed.
Rice. 283. Steering wheel puller: 1 - screw; 2 - capture; 3 - tip
When installing the steering wheel, tighten the nut securing it, ensuring a tightening torque of 59... 79 N·m (6... 8 kgf·m).
To check, adjust and repair the steering gear relief valve when it fails or is unstable:
- drain the oil from the power steering system;
Having removed the seal and uncoiled the plug of the safety valve socket, wash with a rag moistened with kerosene or diesel fuel the boss of the power steering control valve housing, in which the safety valve is located;
Unscrew the plug of the safety valve socket and, having removed the faulty valve, close the hole in the power steering valve body with clean paper or a napkin;
Wash the valve with kerosene and check for nicks and foreign particles on the valve body, the seating edges of the needle valve, on the seat and on the internal surfaces of the hole in the control valve body. Remove foreign particles. Also check the integrity of the rubber O-ring and valve spring;
If an external inspection of the valve cannot reveal a malfunction, check the safety valve (this check can only be performed in specialized workshops equipped for working with hydraulic equipment) in a special device that allows oil to be supplied under pressure to the inlet of the safety valve, such as, for example, a load -measuring stand MT-60 manufactured by “STOLECZNE ZAKLADY BYDOWY MASZYNIKI” (Poland).
At oil pressure up to 6377 kPa (65 kgf/cm2), leakage from under the safety valve is unacceptable. If there are leaks, carefully disassemble the valve and blow out the parts with a stream of compressed air. The valve should open completely at a pressure of 7357.5... 7848 kPa (75... 80 kgf/cm2).
In the absence of a special device, it is permissible to check the correct regulation of the safety valve on a car.
Adjust the valve by rotating the screw plug. After adjustment, lock the screw plug. Seal the locknut with wire and place a seal.
To facilitate assembly and to avoid pinching the sealing ring, lubricate the seat in the hole of the control valve body and the ring itself with PVK grease GOST 19537-74;
- flush and refill the system.
To remove the steering gear:
Having uncoiled and unscrewed the nuts, remove the bipod coupling bolts 9 (see Fig. 270) or, by bending the antennae of the lock washer, unscrew the nut of the upper head of the bipod;
Using a puller, remove the bipod by screwing screw 3 (Fig. 284) into the grip 1 of the puller and resting tip 2 against the end of the bipod shaft (knocking out the bipod can cause breakage of parts);
Disconnect the high and low pressure lines from the steering gear and drain the remaining oil in the pump;
Disconnect the steering propeller shaft from the steering mechanism; to do this, remove the cotter pin, unscrew the wedge nut and knock out the wedge;
Remove the bolts securing the steering gear housing to the front spring bracket and remove the steering gear;
- clean and rinse the outer surface of the steering mechanism;
Drain the remaining oil by turning the steering mechanism with the valve down and turning the bevel gear drive shaft two or three times from one extreme position to the other.
Rice. 284. Steering bipod puller: 1 - grip; 2 - tip; 3 - screw
When installing the steering gear on a vehicle:
Install the mechanism on the front bracket of the left front spring and secure it with bolts with a tightening torque of 275... 314 N·m (28... 32 kgf·m);
- connect the discharge and drain pipelines to the power steering control valve;
Attach the steering cardan shaft to the steering mechanism, having previously aligned the hole in the cardan fork and the flat for the wedge on the drive gear shaft, hammer in the wedge, tighten and pin the nut with a tightening torque of the wedge nut of 13.7... 16.7 Nm ( 1.4... 1.7 kgf m);
- fill in oil and bleed the power steering system (see section “To change the oil”);
Having previously opened the slot of the upper head of the bipod with a wedge, put the steering bipod on the steering gear shaft, insert the coupling bolts, screw the nuts onto the bolts, tighten them and pin them with a tightening torque of 177... 196 N·m (18...20 kgf·m ). The bolt nuts should be located on opposite sides of the bipod head;
Check the tightness of connections and hoses of the hydraulic steering system. Do not allow oil to leak from connections.
Disassembling and checking the steering mechanism
carry out in the following order:
1. After unscrewing the fastening bolts, remove the side cover along with the bipod shaft. When removing the bipod shaft, first clean its splined end.
2. Check the axial movement of the adjusting screw in the bipod shaft. If the movement exceeds 0.15 mm, adjust the axial clearance by selecting a shim. The adjusting screw must have an axial movement relative to the bipod shaft of 0.02... 0.08 mm and rotate smoothly, without jamming. The retaining ring must fit completely into the groove of the bipod shaft. This is necessary for reliable connection of the parts of this assembly.
If necessary, replace the adjusting screw O-ring using a mandrel. After assembly with the side cover, the bipod shaft should rotate freely by hand, and the adjusting screw should remain motionless (check without the locknut).
3. After unscrewing the mounting bolts, remove the front cover. During all subsequent disassembly and assembly operations, remember that turning the steering gear screw out of the ball nut more than two turns from the middle position can lead to the balls falling out and the screw jamming.
4. Unscrew the nuts securing the power steering control valve housing and carefully push the housing forward enough so that it can be rotated relative to the screw without touching the bevel gear housing studs.
5. Check the tightness of the thrust bearing nut and the smooth rotation of the control valve body relative to the screw. The torque required to rotate the control valve body must be equal to 98.1...122.6 N cm (10... 12.5 kgf cm) (during operation, the rotation torque is allowed to drop to 34.3 N cm cm (3.5 kgf cm) If the torque does not correspond to the specified value, adjust the tightening of the thrust bearing nut.
If the valve body does not rotate smoothly (rotation resistance varies), replace the bearings. To adjust the tightening or replace the bearings, it is necessary to press the collar of the nut pressed into the groove of the screw and unscrew the nut, holding the drive gear of the angular gearbox from turning.
WARNING: When removing the thrust bearing nut, be sure to hold the bevel gear drive shaft from turning. Failure to comply with this rule leads to breakage of the antenna of the spring washer 23 (see Fig. 275) and damage to the thread of the screw 17.
When removing the control valve body, make sure that the spool and reaction plungers do not fall out, since during factory assembly each of them is individually matched to its hole.
Do not mix the thrust bearing rings and keep them complete.
6. Check by hand the smooth movement of the reaction plungers and spool in the power steering control valve body. If you feel any jamming or a change in the force required to move the mentioned parts, remove the jammed parts one by one. Eliminate the cause of the jamming, wash and reinstall them.
7. Check the tightness of the check valve by pouring oil into its hole. Oil leakage is only permissible in the form of individual drops.
8. Having unscrewed the fastening bolts and unscrewed the two nuts, remove the bevel gear along with the screw and piston-rack.
9. Use pliers to remove retaining ring 3 (see Fig. 275) and carefully remove the bevel gear from the screw.
10. Check for axial movement of the ball nut relative to the piston-rack. If necessary, tighten or replace the two set screws and unscrew them.
11. Check the fit of the ball nut on the middle part of the helical groove of the screw. The nut should rotate on the screw without jamming, and its axial play relative to the screw should not exceed 0.3 mm.
If the rotation of the screw in the ball nut is not smooth, provided that the axial play does not exceed 0.3 mm, replace the set of balls.
To replace a set of balls, first do the following:
- use a special wrench with a sufficiently large shoulder to unscrew the set screws of the ball nut;
- remove the ball nut and screw from the piston-rack, holding the grooves and balls from falling out;
- remove the grooves, inspect them and, if the tongues are damaged, replace them;
Then, turning the screw relative to the nut in one direction or another, remove the balls and put them in a separate box.
Installation of balls with a diameter difference of more than 0.002 mm is not allowed. Failure to comply with this requirement may result in destruction of the balls and jamming of the steering mechanism.
After replacing the balls, the nut should rotate in the middle part of the screw thread under the influence of a torque of 29.4... 78.5 N m (3... 8 kgf m), the nut should fit freely at the edges.
The raceways on the screw and nut must not be damaged. If the raceways are damaged (dented, burred, etc.), replace the entire screw-ball nut-ball assembly.
12. Inspect the working surfaces of the power steering. If there are individual burrs on the cylinder mirror, remove them with a scraper. Individual longitudinal marks and scratches on the cylinder mirror (without burrs) are not a defective sign.
13. Check the adjustment of the side clearance between the teeth of the bevel gears. The lateral clearance between any pairs of teeth should be within 0.02 ... 0.07 mm, and the rotational moment of the drive gear in the angular gearbox should not exceed 49.1 N cm (5 kgf cm).
The side clearance in the gear teeth of the gearbox is adjusted by moving the drive gear assembly by selecting a pack of gaskets under the flange of the drive gear housing. In this case, at least three gaskets with a thickness of 0.05 mm must be installed.
When bevel gears mesh correctly, the contact pattern should be elliptical and located closer to the inner narrow part of the tooth. It is unacceptable for the contact patch to reach the edges of the tooth.
When disassembling the bevel gear, do not disturb the complete set of the bevel gear housing and the pair of bevel gears.
Reassemble the steering mechanism in a clean environment, in the reverse order of disassembly, in accordance with the following instructions:
1. Wash and dry all parts of the disassembled mechanism; after washing, blow out the internal channels and holes with dry compressed air. Do not wipe parts with a rag, which may leave threads, lint, etc. on them.
2. Before assembly, lubricate all contacting surfaces of the steering mechanism parts with Turbine T n -22 GOST 9972-74 oil or R grade oil.
3. Inspect and replace all rubber sealing parts. The fluoroplastic rings of the piston and screw seals must not be damaged. To facilitate the installation of rubber rings and to avoid pinching them during assembly, it is allowed to use PVK lubricant GOST 19537-74.
4. In case of replacing the cuffs of the bipod shaft and the drive gear shaft of the angular gearbox, press them in smoothly and without distortions, using mandrels. Finally, press the specified cuffs in a package together with the outer cuff and other parts included in the mentioned seal assembly units - until they stop in the mechanism body. When installing the bipod shaft cuffs, their working edges must be protected from damage by the shaft splines.
5. The tightening torque of M8 bolts should be 20.6... 27.5 Nm (2.1... 2.8 kgf m), M10 bolts and nuts - 34.3... 41.2 N m (3.5... 4.2 kgf m). The thrust cover of the driven gear assembly unit of the gearbox must be tightened with a torque of 43.2... 60.8 N·m (4.4... 6.2 kgf·m) and locked by opening its edge into the groove on the bevel gear housing.
The nut for fastening the bearings of the drive gear of the angular gearbox must be tightened to a torque of 39.2... 58.9 N m (4... 6 kgf m) and locked by pressing the nut flange into the groove on the drive gear shaft.
After assembly, the driven and driving gears of the angular gearbox should rotate freely and have no noticeable axial play.
Tighten the magnetic drain plug (with a tapered thread and a cylindrical magnet) to a torque of 33.4... 39.2 N·m (3... 4 kgf·m).
6. Assemble the ball screw pair and install the assembled set into the piston-rack in the following order:
- place a floating sealing sleeve on the screw from the side of its screw groove;
Install the nut on the lower end of the screw, aligning the holes in the nut that the grooves fit into with the helical groove of the screw;
Place twenty-three balls through the hole in the nut facing the bevel gear by turning the screw counterclockwise;
Place eight balls in the grooves folded together and prevent them from falling out by covering the outlets of the gutter with PVK grease GOST 19537-74;
Place the ball grooves into the nut, turning the screw if necessary, and tie the nut around the nut to prevent the grooves from falling out;
Check the torque of the nut on the middle part of the screw (should be equal to 29.4... 78.5 N.cm (3... 8 kgf.cm); if the torque does not correspond to the specified value, replace the set of balls, avoiding mixing the sets;
Press the nut and screw into the hole of the piston-rack by screwing and unscrewing the set screws in two places against the grooves in the piston-rack. The tightening torque of the set screws should be 49.1... 58.9 N·m (5... 6 kgf·m). If the groove in the piston-rack coincides with the screw slot, replace the latter.
Protrusion of the screws above the cylindrical surface of the piston-rack is unacceptable. This will cause scuffing of the working surface of the power steering cylinder.
7. When assembling an angular gearbox with a screw and a floating sealing sleeve, make sure that the retaining ring of the latter is securely installed in the groove of the thrust cover of the angular gearbox. The retaining ring must fit completely into the said groove.
8. Install the piston-rack into the crankcase using a mandrel without distortion.
9. When assembling the power steering control valve, make sure that the groove on the end of the spool is facing the bevel gear, and the chamfers on the reaction plungers are facing outward. After assembly, the spool, check valve, and reaction plungers should move smoothly in the corresponding holes of the control valve body without jamming.
10. When assembling the power steering control valve with the screw, install the thrust bearings so that their large rings face the spool. The spring washer of thrust bearings must be installed with the concave surface towards the bearing. After adjusting the torque required to rotate the control valve body (98.1... 122.6 Ncm (10... 12.5 kgfcm), lock the thrust bearing mounting nut by pressing the nut shoulder into the groove of the steering gear screw.
11. When assembling the adjusting screw and the bipod shaft, ensure that the axial movement of the screw relative to the bipod shaft is 0.02... 0.08 mm by selecting an adjusting washer. If necessary, replace the adjusting screw O-ring using a mandrel.
12. Adjust the gearing in the pair “piston - rack - gear sector of the bipod shaft” in accordance with the instructions stated above. After completing the adjustment of the engagement, tighten the adjusting screw of the bipod by tightening the lock nut with a torque of 58.9... 63.8 N·m (6... 6.5 kgf·m), while holding the adjusting screw from turning.
After assembly, the steering mechanism must meet the following requirements:
1. The full angle of rotation of the bipod shaft must be at least 90°.
2. After rotating the steering gear screw until the piston stops and applying an additional torque of at least 19.6 N·m (2 kgf·m) to the drive gear, the centering springs must ensure its clear return to its original position. This condition must be observed when turning both right and left.
3. The torque applied when rotating the drive gear (or the force on the steering wheel rim applied over a radius of 250 mm) must be:
After turning the drive gear more than two turns in any direction from the middle position - 147... 294 N cm (15... 30 kgf cm [force on the steering wheel rim is 5.9... 11.8 N (0.6... 1.2 kgf)];
When turning the drive gear with a transition through the middle position with a guaranteed gap in the gearing of the rack-piston and the bipod shaft - 196... 441 N cm (20... 45 kgf cm) [the force on the steering wheel rim is 7.8 ... 17.7 N (0.8... 1.8 kgf)];
When turning the drive gear with a transition through the middle position after adjusting the gearing of the rack-piston and bipod shaft - 98.1... 147.2 N cm (10... 15 kgf cm) [at 3.9... 5.9 N (0.4... 0.6 kgf) more than with a guaranteed gap], but not more than 540 N cm. (55 kgf cm) .
4. Additionally, test the steering mechanism on a stand equipped with a pump with a flow rate of at least 9 1/min and providing an oil supply to the hole in the power steering control valve housing. Conduct the test on grade P oil at a temperature not lower than plus 40°C.
Before testing, remove air from the system. Adjust the safety valve of the bench pump to an opening pressure of 5390 kPa (55 kgf/cm2) and check:
Rotation of the drive gear in any direction at a moment of resistance to rotation of the bipod shaft of 0 and 1275 N·m (130 kgf·m) should be smooth, without jamming;
The pressure at the inlet to the power steering control valve with the spool in the neutral position should be no more than 294 kPa (3 kgf/cm2);
- moment on the drive gear with a resistance on the bipod shaft of 1275 N·m (130 kgf·m) - no more than 1766 N·cm (180 kgf·cm);
Leakage at the outlet of the power steering control valve when turning the drive gear all the way to the right or left (measuring time no more than 20 s, measurement starts 5 s after turning the screw all the way) - no more than 1200 cm 3 /min;
Rotation of the bipod shaft from one extreme position to another should occur from a force with a moment of no more than 118 N·m (12 kgf·m).
Adjust the bench pump safety valve to an opening pressure of 90 1/min and check:
Pressure in the discharge line when the drive gear is turned all the way to the right and left; it should be 7355... 7846 kPa (75... 80 kgf/cm2). After removing the force from the screw without braking and stopping the drive gear shaft, the pressure should quickly drop to a value of no more than 294 kPa (3 kgf/cm2);
Tightness of the steering mechanism in both extreme positions of the piston (5 min in each position) at a pressure of 8826 kPa (90 kgf/cm2). Provide pressure by installing a valve on the return line;
Correct inclusion characteristics. The free play on the drive gear shaft (the angle of rotation of the shaft before the pressure in the pressure line increases by 78.5 kPa (0.8 kgf/cm 2) should be 3... 5° in each direction. The total free play (the sum of the angles to the right and left) no more than 10° is allowed.
To remove the power steering pump
during repair:
- tilt the cabin to the first position (42°);
Unscrew the magnetic plug and drain the oil from the steering gear housing; for more complete drainage, turn the steering wheel two or three times from one extreme position to the other;
- disconnect the low and high pressure pipelines from the pump;
- disconnect the pipeline connecting the expansion tank to the left water pipe;
- Unscrew the pump mounting bolts.
Remove the pump.
To disassemble and check the pump:
- remove the tank cap and unscrew the filter from the manifold;
- unscrew the fastening bolts and remove the tank with the manifold, remove the tube;
Check for flatness of the manifold bearing surface on the control plate. The non-flatness of the specified surface is allowed no more than 0.1 mm with a roughness of 6.3 nm. If greater non-flatness is detected, mill the supporting surface of the collector, then check it on the plate, and replace the paronite gasket;
Place the pump in a vice so that its shaft is positioned vertically, with the gear facing down, remove the four coupling bolts and, holding the bypass valve from falling out, remove the pump cover;
Check the condition of the sealing surface of the seat for connecting the high pressure pipeline.
If the specified surface is significantly dented, which can cause a leak, use an M6 bolt to remove the seat, having previously cut a thread in it. To prevent chips from getting into the valve, place grease in the seat hole. When pressing a new seat, use a mandrel;
Check that the bypass valve moves easily and smoothly in the cover hole under its own weight. When checking, the valve spring must be removed. If necessary, wash the valve and the hole in the lid with acetone, cleaning their working surfaces from adhering foreign particles or burrs.
The valve and cover are individually selected at the factory, so do not disassemble this pair (the gap in it on the new pump is 0.013... 0.023 mm).
If unacceptable wear is detected in this pair (the pump does not provide the required flow), replace the valve and cover as a whole;
- check the pressure setting of the pump safety valve and the tightness of its seat.
Check the valve in a special device that allows you to supply oil under pressure to the hole in its seat, for example, a load-measuring stand MT-60 (Poland).
At oil pressure up to 7355 kPa (75 kgf/cm2), leakage from under the safety valve is unacceptable. If there are leaks, check the condition of the valve parts. To do this, unscrew the valve seat, keeping the existing adjusting shims, rinse the cavity in which the spring and ball are located, and check the cleanliness of the hole in the seat.
Check the integrity of the spring and assemble the valve by tightening its seat with a torque of 14.7... 19.6 N·m (1.5...2 kgf·m).
The valve should open at a pressure of 8336... 8826 kPa (85... 90 kgf/cm2) and allow a continuous stream of oil to pass through. If the valve operates at a lower pressure, then the cause of the defect may be the settling of its spring due to a previous overheating of the pump. In this case, in order to eliminate the indicated defect, it is allowed to remove the adjusting shims from under the safety valve seat.
It should be borne in mind that removing one gasket with a thickness of 0.5 or 0.7 mm gives an increase in pressure, respectively, by approximately 686.5 or 980.7 kPa (7 or 10 kgf/cm2). It is not recommended to remove the last gasket from under the seat, since the absence of a gasket can lead to spontaneous loosening of the seats during vehicle operation.
In the absence of the special device mentioned above, the correct regulation of the safety valve can be checked on a stand assembled with a pump, including an electric motor with a power of at least 2.5 kW, driving the pump being tested through a gear drive. The pump shaft rotation speed is 600 min -1. A pressure gauge with a measurement limit of 9807 kPa (100 kgf/cm2) and a valve must be installed in the pump pressure line. The length of the pipeline from the valve to the tank is at least 1 m. Before checking the pump, you should run it in for 10... 15 minutes, gradually increasing the pressure with the valve to 4904... 5349 kPa (50... 55 kgf/cm 2);
- insert the valve with the spring into the hole in the cover and once again make sure that its movements are smooth.
During all further operations of disassembling and subsequent assembly of parts of the pump pump unit, it should be kept in mind that the stator, rotor and pump blades are selected as a complete set at the manufacturer; When disassembling, do not disturb their completeness, do not swap the blades. When replacing the stator, rotor and blades, install them as a set;
Mark the relative positions of the distribution disk relative to the stator, and the latter - relative to the pump housing and remove them from the pins. The arrow on the stator indicates the direction of rotation of the pump shaft;
- remove the rotor along with the blades, making sure that the blades do not fall out of their grooves;
Check the ease and smooth movement of the blades in the rotor grooves. If you find dirt or other foreign particles on the surfaces of mating pairs, remove the blades from the grooves and wash the parts with gasoline;
To replace bearings or cuffs, if necessary, install the pump housing in a vice so that its shaft is positioned vertically, with the gear facing up, unscrew and unscrew the nut, holding the gear from turning; remove the gear together with the washer and remove the key from the shaft groove, as well as the ball bearing retaining ring. Using a puller, remove the shaft along with the bearing and oil ring from the pump housing.
Replace worn parts and reinstall the shaft; Check the smooth rotation of the shaft, then install the retaining ring.
When assembling the pump
Install the rotor with blades, stator and distribution disk according to the marks made during disassembly and the arrow on the stator indicating the direction of rotation. In this case, the chamfer of the rotor spline hole should face the pump housing.
When installing a cap with a bypass valve, the hexagon of the safety valve seat must be directed toward the inside of the hole.
The tightening torque of the safety valve seat is 14.7... 19.6 N m (1.5... 2 kgf m).
When tightening the pump cover bolts, pay attention to the correct relative position of the mating flanges for installing the pump reservoir. Their mutual distortion is not allowed.
Run the repaired pump on the stand using oil R or Turbine T n -22 in the mode specified in the table. 44.
TABLE 44
| Time, min |
Oil pressure, kPa (kgf/cm2) |
Pump shaft rotation speed, min -1 |
| 1
|
147,1 (1,5)
|
845
|
| 2
|
490 (5)
|
845
|
| 3
|
980,7 (10)
|
1270
|
| 5
|
1961,4 (20)
|
1680
|
| 3
|
2942,1 (30)
|
2600
|
In this case, the oil temperature should be 45... 50°C. A short-term increase in temperature at the end of running-in to 55°C is allowed.
After running in the pump, check:
The flow rate at a pump shaft speed of 600 min -1 and 2000 min -1 and a pressure of 5394 kPa (55 kgf/cm 2) must be, respectively, at least 9 1/min and 13... 17 1/min (check time no more than 30 With);
The pressure in the discharge cavities of the pump at a rotation speed of 600 rpm and the outlet is closed should be 8334... 8826 kPa (85... 90 kgf/cm2) (check time no more than 15 s);
- the presence of vibration, sharp noise, foam in the tank is not allowed;
- oil leakage through the connection points and the pump shaft cuff is not allowed.
After the test, drain the oil and wash the pump filter.
The trouble-free operation of the steering system is determined both by the serviceability of the elements included in it and the correct operation of other assembly units of the car, therefore, when determining the causes of a malfunction in the steering system, it should be borne in mind that the reasons for the deterioration of the vehicle's motion stability (the car does not hold the road well) may be be:
- incorrect wheel balancing;
- insufficient or different tire pressure;
- play in the hub bearings and improper tightening of the nuts securing the wheels to the hubs;
- faulty shock absorbers;
- incorrect installation of the steered wheels (installation angles and toe-in do not correspond to the recommended ones).
The reasons for the deterioration of the self-return of the steered wheels to the neutral position (the driver is forced to force them to return to the middle position all the time) may be:
- lack of lubrication and high friction in the hinges of the steering knuckles;
- insufficient tire pressure.
The reasons for increased steering force may be:
- insufficient tire pressure;
Lack of lubrication in the pivot assemblies of the steering knuckles (especially in the thrust bearings), in the wheel hubs and in the steering rod joints;
- retightening of the front wheel hub bearings;
- reupholstering the steering column bearings.
If you find any defect in the steering system, do not rush to disassemble its mechanism. Try to first determine the possible cause of the malfunction or failure. Remember that unnecessary disassembly of the steering mechanism or pump can lead to leaks and more serious problems. Disassembly and reassembly of the steering gear and pump should only be carried out by a qualified mechanic in a completely clean environment.
TABLE 43
POSSIBLE MALFUNCTIONS OF THE STEERING SYSTEM AND WAYS TO ELIMINATE THEM
| Cause of malfunction
|
Elimination method
|
| Unstable movement of the vehicle on the road (regular additional work of the steering wheel is required to maintain this direction of movement)
|
| Increased free play of the steering wheel |
Adjust the free play of the steering wheel |
| Parts of the steering gear screw pair are worn out |
Replace the ball screw kit |
|
Adjust the tightening of the nut |
|
|
| Damaged internal steering gear seals |
Replace faulty seal parts |
| Insufficient or uneven operation of the hydraulic booster
|
|
|
| Presence of air in the system (foam in the tank, cloudy oil) |
Remove the air. If air cannot be removed, check the tightness of all connections, remove and wash the filter, check the integrity of the filter elements and gaskets under the manifold, as well as the pump reservoir. Make sure that the supporting surface of the manifold is flat and that the mating flanges of the cover and pump housing are correctly positioned (for installation of the pump reservoir) *
. Check the tightness of the four manifold mounting bolts and, if all of the above is correct, fill in oil and bleed the system again Adjust the steering |
| Excessive tension in the steering gear gear |
Adjust the steering mechanism using the adjusting screw, bring the force on the steering wheel rim to normal |
| The pump does not develop the required flow due to clogging of the filter or wear of the parts of the pumping unit |
Wash the filter and disassemble the pump to check its parts. Replace the pump if necessary |
| Increased internal oil leaks in the steering mechanism due to wear or damage to the internal seals |
Disassemble the mechanism, replace o-rings or other damaged sealing elements |
| Periodic freezing of the bypass valve due to contamination |
Disassemble the pump, wash the bypass valve and the hole in the pump cover with acetone, cleaning their working surfaces from burrs and foreign particles
|
| Steering gear check valve leaking |
Repair leaking check valve |
| The steering screw thrust bearing nut is loose |
Adjust the tightening of the nut |
| The adjustment of the steering gear safety valve spring is incorrect or the valve is leaking due to contamination or nicks. |
Adjust the valve, eliminate leaks |
| Complete absence of gain at various engine speeds
|
| The pump safety valve seat is loose or the valve spring is broken |
Disassemble the pump, tighten the seat or replace the valve spring |
| Bypass valve stuck or faulty steering check valve |
Disassemble the pump and wash the valve, eliminate the leakage of the check valve |
| Broken steering safety valve spring |
Replace the spring and adjust the valve |
| The force on the steering wheel is not the same when turning left and right
|
| Damaged internal seals of the steering screw and piston |
Replace faulty screw and piston seal parts |
| Steering mechanism jams when turning
|
| Seized spool or reaction plungers in the power steering valve body |
Remove jams, wash parts |
| Wear of the parts connecting the adjusting screw to the bipod shaft or the gearing of the steering mechanism |
Adjust the axial clearance in the connection by selecting an adjusting washer. If the gearing or connection of the adjusting screw with the bipod shaft is worn beyond the permissible level, replace the steering mechanism |
| Knock in the steering mechanism or in the propeller shaft of the steering column
|
| Increased clearance in the steering gear gear |
Adjust the gap with the adjusting screw |
| The nuts of the steering arm connection bolts are not tightened |
Tighten the nuts |
| The nuts of the wedges securing the propeller shaft forks are not tightened or the spline connection is worn |
Tighten the nuts. Replace worn parts |
| Increased noise during pump operation
|
| Insufficient oil level in the pump reservoir |
Bring the oil level in the pump reservoir to normal |
|
Wash or replace the filter |
| Presence of air in the hydraulic system (foam in the reservoir, cloudy oil) |
Remove air |
| |
Remove bent or replace gasket |
| Oil release through pump reservoir cap safety valve
|
| Excessively high oil level in the pump reservoir |
Bring the oil level to normal |
| Pump filter clogged or damaged |
Wash or replace the filter |
| The manifold is bent or its gasket is damaged |
Remove bent or replace gasket, bleed air from system |
| Constant drop in oil level in the pump reservoir
|
| Oil leakage into the engine due to damage to the pump shaft cuff |
Remove the pump from the engine and replace the cuff |
| Breakage of the front cover of the steering mechanism (during the cold season)
|
| The steering hydraulic system is filled with oil that is not recommended in the lubrication chart. |
Replace the cover. Fill with oil corresponding to the lubrication chart |
| Substitute oil was not replaced during seasonal maintenance |
Replace the cover. Change the oil to the appropriate one for the season |
| There was (or got in during operation) water in the oil, and during long-term parking in the cold with the engine turned off, ice plugs formed |
Replace the cap, replace the existing oil in the system with oil tested for the absence of water, remove air from the system. The type of oil must match the season! |
, Power steering Kamaz- hydraulic system, part of the car that makes up the steering mechanism. Power steering is useful because it reduces the effort when interacting with the steering wheel, as well as when driving a car, it also eliminates shocks on uneven roads, and controls movement if something happens to the tires, for example, they are damaged.
Kamaz power steering or power steering consists of different elements, each of which performs its own functions:
Electrical unit- regulates the operation of the hydraulic booster electronically.
Working fluid- acts as a pressure transmitter to the hydraulic cylinder from the pump, and also lubricates elements, in particular friction pairs.
Connecting hoses- serve to connect the pump, hydraulic cylinder, and distributor together.
Hydraulic cylinder- consists of a rod, as well as a chrome-plated piston. The pressure that the fluid creates is converted into energy that pushes the piston.
Distributor- distributes liquid throughout the hydraulic system, throughout all its cavities.
Kamaz power steering pump- pumps fluid and circulates it throughout the hydraulic system. The so-called heart of the hydraulic system.
It must be remembered that checking and adjusting the Kamaz power steering is possible only under one condition - when the engine is turned off, as well as when the steering rod (longitudinal) is also turned off.
Checking and adjusting Kamaz power steering:
Steering wheel- you need to measure the force on the steering wheel itself
Wheels- you need to check what pressure the air creates in the wheel, as well as what kind of balancing the wheels have, you also need to check whether there is lubrication in the steering system.
Oil- you need to open the pump reservoir where the oil is located, and look for the presence of air, there should not be any air in the system, and the oil should not leak or leak, you need to eliminate all oil leaks, look at the oil for contamination with mechanical particles, and see if there is sediment , both on the pump filter and on the barrel itself - it shouldn’t be there.
Steering rods- view the bearings on the wheel hubs, also view all the steering rods, see how the shock absorbers work.
If you monitor the power steering system, carry out maintenance on it, and operate it under normal conditions, then the Kamaz power steering device can work reliably and for a very long time.
What malfunctions can occur in Kamaz power steering?
1. Power steering started losing oil from the hydraulic system.
2. The steering wheel no longer turns easily in one direction and the other, it began to turn hard.
3. There are extraneous noises or loud noises when the pump is running.
4. The steering wheel turns quickly, and the steering mechanism itself is slow or difficult to respond.
5. They started transmitting to the steering wheel some shocks or the steering wheel began to rotate and oscillate.
6. It became difficult to hold the steering wheel when you go straight.
7. The steering wheel began to lag, on its return stroke.
To produce power steering repair, you need to carry out a full diagnosis, and only after that proceed with repairs. The first step is to look at the pressure in the steering system when the steering wheel is in one extreme position and the other, you should also look at what maximum pressure the pump receives and what its fluid flow is.
If you see that some the part is worn out, then you need to replace it, just buy a new one. If the hydraulic booster is in the car, then you will not be able to repair it because it needs to be removed and then repaired. It is worth remembering that self-repair is fraught with consequences, so complete or partial disassembly should be carried out by specialists, in specialized enterprises that carry out repairs, like our Hydro Special Market.
How to change oil in power steering Kamaz
To change the power steering oil, you need to bleed it; this action will remove air from the system. Air should not be left in the system.
1. First required on the steering gear open the valve, it is also called a bypass valve.
2. After this compress the centering springs. This can be done by turning the steering wheel to the left all the way.
3. Fill the pump with oil
4. The power apparatus must be turned on, and at this time you add oil slowly and gradually, and see if air bubbles come out of the hose. If the bubbles stop coming, it means enough.
5. Screw the valve back(bypass valve)
6. Again compress the centering springs, only now you need to turn the steering wheel to the right to the limit, and the springs should compress, and immediately return it back to the left all the way, twist the bypass valve again to see if any air bubbles are released. After all the air has come out, the valve can be screwed back on.
7. Do the action from the previous point until all the air comes out, but only oil will flow from the valve.
| Number on the diagram
|
Designation
|
| 1
|
Steering wheel |
| 2
|
Hydraulic Filter Safety Valve Spring |
| 3
|
Filter |
| 4
|
Power steering pump |
| 5
|
Bypass valve |
| 6
|
Bipod shaft with gear sector |
| 7
|
Rear power steering cavity |
| 8
|
Piston-rack |
| 9
|
Bipod |
| 10
|
Longitudinal thrust |
| 11
|
Lateral thrust |
| 12
|
Car front wheel |
| 13
|
Magnetic plug |
| 14
|
Ball nut |
| 15
|
Screw |
| 16
|
Steering gear housing |
| 17
|
Check valve |
| 18
|
Safety valve on steering gear |
| 19
|
Power steering valve |
| 20
|
Spool |
| 21
|
Thrust bearing |
| 22
|
Jet plunger |
| 23
|
Centering spring |
| 24
|
Angular reducer |
| 25
|
Power steering front cavity |
| 26
|
Discharge line |
| 27
|
Cardan shaft |
| 28
|
Radiator |
| 29
|
Steering column |
| 30
|
Filling filter |
| 31
|
Power steering pump reservoir |
| 32
|
Drain line |
| 33
|
Bypass valve spring |
| 34
|
Safety valve on the pump |
| 35
|
Bypass valve |
| A, B |
Throttling holes |
| I |
Drive straight or neutral |
| II |
Turn right |
| III |
Turn left |
How to assemble or disassemble the power steering power steering KAMAZ 4310 - Assembly diagram of the power steering power steering KAMAZ 4310
Steering control assembly 4310-3400020 - Steering mechanism 53212-3400020
| Number on the diagram
|
Designation
|
Catalog number
|
| 1
|
Bolt M8-6gх30 |
853354
|
| 2
|
Spring washer 8 |
1/05166/73
|
| 3
|
Front cover |
4310-3401079
|
| 4
|
Ring sealing |
864201
|
| 5
|
Ring sealing |
864201
|
| 6
|
Nut M25x1.5-6N |
853512
|
| 7
|
Spring washer |
5320-3401373
|
| 8
|
Nut M10x1.25-6N |
1/21647/21
|
| 9
|
Spring washer 10 |
1/05168/73
|
| 10
|
Thrust bearing |
864650
|
| 11
|
Thrust bearing |
864650
|
| 12
|
Steering mechanism assembly |
4310-3400020
|
| 13
|
Angular gearbox assembly |
4310-3401710
|
| 14
|
Steering bipod |
4310-3401090
|
| 15
|
Washer |
853631
|
| 16
|
screw |
853567
|
| 17
|
Blank ball |
64707
|
| 18
|
Bolt M10x1.25-6gx30 |
1/13069/21
|
| 19
|
Spring washer 10 |
1/05168/73
|
| 20
|
Nut M14x1.5-6N OST 37.001.197-75 |
251648
|
| 21
|
Side cover |
4310-3401083
|
| 22
|
Sealing cuff |
4310-3401029
|
| 23
|
Ring sealing |
864206
|
| 24
|
Steering gear sealing ring |
864203
|
| 25
|
Sleeve |
5320-3401791
|
| 26
|
Ring sealing |
864204
|
| 27
|
Resistant ring |
862803
|
| 28
|
Adjusting washer |
5320-3401140
|
| 29
|
Adjusting washer (453471205) |
5320-3401141
|
| 30
|
Adjusting washer |
5320-3401142
|
| 31
|
Washer |
5320-3401144
|
| 32
|
Adjustment screw |
5320-3401163
|
| 33
|
Thrust washer |
5320-3401176
|
| 34
|
Bipod shaft |
4310-3401065
|
| 35
|
Bipod shaft sealing collar |
4310-3401029-10
|
| 36
|
Thrust washer for bipod shaft sealing collar |
4310-3401789
|
| 37
|
Steering gear housing |
4310-3401015
|
| 38
|
|
864207
|
| 39
|
Steering gear sealing ring |
864207
|
| 40
|
Bypass valve |
5320-3401371
|
| 41
|
Valve cap |
5320-3401377
|
| 42
|
Rear steering housing cover |
4310-3401529
|
| 43
|
Spring washer 10 |
1/05168/73
|
| 44
|
Bolt M10x1.25-6gx30 |
1/13069/21
|
| 45
|
Crankcase bushing |
4310-3401076
|
| 46
|
Bipod shaft cuff assembly |
864190
|
| 47
|
Resistant ring |
864194
|
| 48
|
Outer cuff of shaft seal assembly |
4310-3401030
|
| 49
|
Blank ball |
864707
|
| 50
|
Magnetic plug assembly |
2101-2401046
|
| 51
|
Set screw |
4310-3401417
|
| 52
|
Rack-piston |
4310-3401411
|
| 53
|
Ball nut |
5320-3401038
|
| 54
|
Blank ball |
864707
|
| 55
|
Ball nut groove |
5320-3401179
|
| 56
|
O-ring for piston rack |
4310-3401415
|
| 57
|
Spacer ring |
864208
|
Repair GUR KamAZ 5320- Diagram of the Kamaz 5320 steering column - Diagram of the power steering 5320
- In a vice, you need to firmly secure the steering mechanism with a built-in hydraulic booster, and set the bipod shaft to the middle position.
- Next, you need to remove the side cover, which is attached to a nut and bolts with washers. The cover is usually removed from the bipod shaft.
- After this, you need to pull out the O-rings and cuff. To do this, you need to hold the shaft a little, unscrew the screw, and remove the cover.
- You can't just remove the retaining ring. To do this, you need pliers that are designed specifically for such operations, their catalog number is I-801.23.000
- After the retaining ring, you must first remove the washers, and then the O-rings.
- To remove the O-ring and cover, you need to unscrew the bolts and remove them from the front cover along with the fastening washers.
- To prevent balls from falling out of the ball nut, you need to protect the shaft so that it does not turn, fix it in such a way that it does not move. This refers to the drive gear shaft on the bevel gear.
- The shaft is also fixed so as not to break the antennae on the washer, and so that the threads on the screw do not fail or become damaged, or the screw itself does not catch the wedge.
- Next, we roll up the nut and begin to remove the washer, then the bearing (the very first one).
- The bolts, washers and nuts on the power steering control valve mount should also be removed.
- Be careful not to let the jet plungers fall out of the control valve.
Disassembling the Kamaz power steering pump. What is inside?
- The bearing (second) needs to be removed from the screw, and the control valve, completely assembled, needs to be removed from the screw.
- After the previous manipulations, we need to remove the sealing rings from the gearbox, from its high-pressure channels.
- To remove the bevel gear assembly with screw and piston rack, you need to unscrew the bolts and washers, as well as the nuts.
How to remove the set screws - a special device (device). Also suitable for pressing out ball nuts.
- To install a piston-rack, as well as a screw with a spacer ring, in a vice, they need to be pulled out or removed from the bevel gear.
- The picture above shows a tool used to remove the screws and press out the ball nut.
- After this, you need to hold the grooves so that they do not fall out, twist the screw from the piston.
- Prepare some kind of bowl for the balls. We take out the grooves and turn the screw so that the balls fall out. The total number of balls is thirty-one (31). In the same container with balls we put a ball nut and a screw. If you put them in different containers, this set may become disjointed and you simply won’t be able to put it back together.
- After the previous step, you need to remove the floating bushing.
- Remove the sealing ring.
- Remove the retaining ring.
- The drain plug is twisted off the crankcase.
- The complete bypass valve is unscrewed from the crankcase, after the drain plug.
- Remove the thrust ring.
- Remove the cuffs.
- Press out the bushing.
- Remove the back cover with the O-ring, having previously removed the bolts and washers from the back cover.
Repairing the KAMAZ steering pump and how to bleed the power steering
- The angular gearbox also needs to be secured in a vice.
- The screws and washers are removed from the fastening on the gear (drive) housing cover.
- After this, remove the protective cap and then remove the lid.
- Next, remove the drive gear and the complete housing, but before that you need to remove the thrust ring, as well as the O-ring, as well as the cuff.
- To remove the sealing ring from the housing, as well as pull out the gear and bearing from there, you must first tighten the nut.
- Next comes the second bearing; it is pressed out of the housing.
- After this, we take a puller and press the bearing out of the gear shaft.
To remove thrust cover, we need a special key, it is shown in the picture above. To begin with, we remove the seal ring, then press out the complete gear (driven) together with all bearings, after which remove the thrust ring. The bearings need to be pressed off the gear shaft; this can be done using a puller. be careful with the fact that the gears cannot be disassembled, neither the driving nor the driven.
Jet plungers must be removed from the control valve body. The check valve with spool and reaction springs is also removed from there.
Remember what is required marking jet plungers marker or corrector, because they are not dismantled, because the spool and, accordingly, the plungers are selected specifically for the holes on the valve body.
If you need to replace any parts or clean them, then you need disassemble and check valve.
To extract ball, you need to manipulate the extension and bending of the cotter pin.
After the parts have been removed, they need to be blast with air under pressure, and wash thoroughly.
Defective parts. How to reject parts. Rejection of Kamaz parts.
If you see that on needle bearings there is wear or any dimples or holes, then it all goes in the trash.
If you see that on rings, there are also some mechanical flaws on their working surfaces, this can also be thrown out and replaced with a new one.
If you see that on bearings If the rings are difficult to turn, they also need to be replaced. The axial clearance should not exceed 0.3 mm. You can determine it with a probe.
You need to look carefully at steering gear housing, because he can also be thrown into marriage. This can be determined if cracks, breaks begin to appear on it, it is warped, or the holes on it begin to wear out by more than 105.05 mm (if we are talking about a piston rack) or up to 58.04 mm (if we are talking about a bushing). If you see that there are burrs on the cylinder mirror, they can be repaired using mechanical processing.
If on piston-rack, on the working surface of the teeth, you see chips, chipping, breaks, cracks, or wear on the outer diameter of more than 104 mm or wear of the groove up to 93.45 mm, then all this is also rejected. If the thread suddenly breaks, it can not be rejected, but repaired or restored.
If on Vale bipod or you also find chips, chipping, breaks, cracks or visible wear on the surfaces of the teeth, then it is also rejected. To check this, the wear along the outer diameter must be no less than 57.92 mm, and the groove for the seal ring must be no more than 1.85 mm in width.
A. If on steering screw you will see broken parts, cracks, dents from balls, or the surface has become bulging, but the screw needs to be locked.
a. Ditches must be no more than 5.5 mm
b. May still wear out splines. The width must be no less than 5.95 mm
c. Seal ring grooves should be no more than 2.5 mm
d. Outside diameter necks must be no less than 29.9 mm
B. If thread worn out or torn, it can be restored.
If on housing on bevel gear If there are any breaks, the holes for the bearings are worn out by more than 80.05 mm, there are cracks, then it can be thrown out or sent for rejection. If the threads are worn or broken, they can be repaired.
If on drive gear there are breaks, breaks, cavities on the teeth, cracks, or the teeth are worn out, if the shaft journals on the outside of the diameter of the larger journal are not less than 25.0 mm and at least 21.97 mm, or if the splines are twisted, then it is rejected.
If on driven gear there are breaks, breaks, cavities on the teeth, cracks, or the teeth are worn out; if the shaft has worn out at least 50.007 mm in outside diameter and the spline cavities are more than 6.08 mm in width, then it is rejected.
If on thrust nut If there are breaks, breaks, or cracks, if the width of the groove is more than 2.3 mm, then it can be rejected. If the thread is broken, it can be restored.
If on floating bushing there are breaks, breaks, cracks, or the diameter has increased to 30.043 mm, then it must be rejected.
If on the body power steering valve there are breaks, breaks, cracks, the surface has been lifted ( A, C) - in the figure above, or the edge has begun to collapse ( B), then the valve body can be rejected. Replacing the valve seat is used if the surface has become oval or nicks have appeared ( H). The figure shows the threads ( D, E, F), if they are torn off, they can be restored.
If on valve spool If the power steering is broken, chipped, cracked, or the surface is bulging, then it can be rejected.
If it's broken needle on safety valve, or is bent, or there are some extra particles on it, or the surface has begun to wear unevenly, then it can be rejected.
Power steering 4310 adjusting the bipod shaft and correct installation of the bipod
Assembling the power steering steering mechanism KamAZ 4310, KamAZ 5320, and any other KamAZ
When is it produced? steering gear assembly into the check valve (its body), then put a ball there and install the cotter pin. According to the size of the outer surface, the tips of the cotter pin are bent into the groove of the housing ring. Also, be careful, the cotter pin cannot be reused, and the ends bent from it cannot protrude.
Spool must be inserted into the control valve body, with a groove towards the bevel gear. When the spool moves, its movements should be as smooth as possible, there should be no stops or jams. The check valve, springs and plungers are inserted into the holes of the control valve (which are blind). In the holes that are through, you need to insert springs with plungers, 2 pieces each. You need to look at the marks on the plungers, and find their chamfers, the outer side, and move along the marks on the outer side as slowly as possible.
O-ring you need to put the adjustment screw on it. You need to find a socket on the valve body, put a spring there, as well as a needle, and tighten the adjusting screw, screw the nut on top.
driven gear. A bearing must be installed and pressed onto this gear, then a bushing, then another bearing, using a groove on the outside of the race, and a ring (thrust) is installed in this groove. The entire gear assembly is placed in the gearbox housing. The sealing ring is placed on the cover (thrust), the cover is screwed onto the gear housing until it stops, pressing the edge on the shoulder of the housing on the gearbox into the cover, or rather into its slot. The bearing should be pressed into the gear (drive) housing. Next, these actions occur with the second bearing, they are pressed into the housing, and a sealing ring is installed.
Need to check how the gear moves. She should walk with ease. This is checked by tightening the nut. There should also be no movement along the axis, and after making sure of this, press the collar on the nut into the gear shaft, into its groove.
IN drive gear You need to press a cuff onto the cover of its body, and then a washer and a thrust ring.
Gaskets It is also necessary to install it on the upper flange in the gearbox housing; after the gaskets, install the gear (drive), in full assembly, the cover from its housing, also in full assembly, and adjust the gearing on the gears.
To adjust the side clearance on the gears, in their engagements, you need to select gaskets. The thickness of the gaskets should not exceed 0.05 mm, no less than 3 pcs. Between a pair of teeth, the side gap should be no more than 0.1 mm. The way to check the contact patch is to see where it is located. It should be exactly in the middle of the tooth. The torque with which the gear rotates should be no more than 49 N×cm or 5 kgf×m. After adjusting the gearing on the gears, you need to put on the cover, attach it with three bolts and washers, put on an O-ring, and a cap for protection.
After the cuff and bushing have been pressed into the crankcase itself, you can install ring (thrust). The washer must be installed on the opposite side of the crankcase, the cuff must be pressed, and a sealing ring must be inserted into the groove of the cover. The screw itself requires a sealing ring, a retaining ring, a nut, and a bushing. We take the ball nut, look at its chamfer, and install it towards the screw groove. And the bushing needs to be placed against the screw slots, with its flat side.
The hydraulic steering control system is an integral part of any KAMAZ, since without it, steering the vehicle will be, if not impossible, then very difficult. Thanks to this unit, the driver can turn the steering wheel with greater ease. You can learn more about what the KAMAZ power steering system is and how to de-air it from this material.
[Hide]
Characteristics of power steering
First, let's look at the main characteristics of the power steering on a KAMAZ 6520 or any other model. Let's start with the purpose and device.
Purpose
The main purpose of the power steering system is to minimize the effort used to turn the steering wheel when steering, as well as performing many maneuvers when driving at low speeds. In addition, thanks to the power steering system, the impact on the steering wheel will be more noticeable if the car is moving at high speed. If the power steering fails for some reason, this will result in the driver having to exert significantly more effort to turn the steering wheel.
Device
Now let's briefly look at the power steering device.
This system consists of the following elements:
- Switchgear. This component is used to direct the flow of working fluids, in particular hydraulic oil, into the lines and cavities of the system.
- Hydraulic cylinder. This device performs the function of converting hydraulic pressure into mechanical work of pistons and rods.
- The working material in this case is hydraulic fluid. With its help, force is transferred from the pump to the hydraulic cylinder. In addition, thanks to the liquid, all rubbing components and components of the system are lubricated.
- KAMAZ power steering pump. Thanks to this device, the pressure required for normal operation is constantly maintained in the system. This element is also used to circulate the working fluid.
- Connecting elements or lines. They are used to bring together all the working components of the system.
- Control device or electronic unit. With its help, direction and adjustment of the operation of the amplifier are carried out.
Photo gallery “Main elements of the power steering system”
Features of the pump
The pumping device is installed in the collapse of the BC. Domestic trucks use a gear top drive, but the device itself is of the blade type. In accordance with the technical documentation, this unit is characterized by double action, that is, with one turn of the steering wheel it carries out two cycles of suction and discharge.
Let's take a brief look at the operating principle. When the wheel turns, the rotor blades begin to rotate, which, in turn, are pressed against the stator device. Working fluid begins to flow into those blades that, when pressed, coincide with the holes on the body. Further, thanks to the same blades, the consumable material enters the narrower holes that exist between the stator and the rotor.
At the moment when the working surfaces can coincide with the holes on the distribution disk, the consumable material will come out beyond it. Next, the oil will pass through the lower valve; for this, high pressure is formed in the system.
The working fluid, leaving the cavity behind the distribution disk, will flow onto the rotor blades, as a result of which they will be pressed even more tightly against the stator plane. The process of pumping the substance, as well as its absorption, is carried out simultaneously in two places. As the number of revolutions of the rotor device increases, liquid from the surface behind the disk will not pass through the calibration hole. By creating pressure in the system, the bypass valve is opened, and part of the consumable material, through the manifold, is again supplied to the suction surface (the author of the video about replacing the hydraulic booster on a KAMAZ is Mathur Malay).
Common power steering faults
It must be said right away that repairing KAMAZ power steering is a procedure that our compatriots do not encounter so often. If the driver follows the basic rules for operating the unit, and also carries out its maintenance in a timely manner, then the likelihood that it will fail will be minimized. As practice shows, problems with the performance of the hydraulic booster mainly arise in the cold season. In general, all malfunctions can be divided into mechanical and hydraulic failures, both of which can occur in any part of the device.
As you know, any hydraulic system most often exhibits malfunctions in frosty conditions, in particular, temperature changes. After all, you need to remember that the pumping device pumps high pressure, so if the viscosity of the liquid in the system increases, this will lead to the squeezing out of the seals and, accordingly, its leakage. The problem of oil seals is especially evident in cars whose drivers do not follow operating rules, for example, leaving the car in a parking lot with the wheels twisted. This will lead to the fact that after starting the engine, the pressure will increase only on one side, accordingly, the oil seal will squeeze out in any case.
As for the warm season, in summer malfunctions usually appear as a result of dirt and dust getting into the system. If any part is depressurized, the wear of the bushings, as well as the rods, will be faster. The rods usually rust quite quickly, resulting in accelerated wear of the bushings. When operating a car with such a problem, after several hundred kilometers, there will be a large gap between these elements, and this, in turn, will lead to the steering rack starting to make a knock (author of a video about repairing the system in a garage - channel EIGHT ATMOSPHERE).
How to remove an air lock from the system?
The need to bleed the system usually arises after refueling it or eliminating breakdowns in the operation of the unit. Air entering the lines leads to less efficient operation of the hydraulic booster, so the only solution in this case is to remove the air.
So, how to bleed the power steering:
- First you need to move the front axle so that the car's wheels do not touch the ground. Using a jack, you should place supports under the beam on both sides. If the wheels are on the ground, bleeding of the system cannot be started.
- Then you need to remove the filler cap of the expansion tank located under the hood.
- Next, the rubberized cap should be removed from the bypass valve, and an elastic pipe should be installed on its head. In this case, its open part should be lowered into a glass container, the volume of which will be at least half a liter. The vessel itself should be filled halfway with the working fluid.
- Then the bypass valve should be opened slightly, half a turn.
- After completing these steps, turn the steering wheel to the left all the way. After this, the working fluid is poured into the expansion tank until its level decreases.
- Then you need to start the power unit, and while it is operating at minimum speed, pour a little liquid into the expansion tank, but without allowing the level to drop. Do this until bubbles stop coming out of the pipe that is installed on the bypass valve. After this, the valve itself can be closed.
- Next, the steering wheel should be turned all the way to the right, and then to the left. And holding the steering wheel in this position, again unscrew the bypass valve halfway and observe whether bubbles come out of the pipe. When they stop coming out, the valve can be tightened.
- This operation must be carried out several times, ultimately a clear liquid will come out of the valve, in which any impurities or air bubbles should be absent. If bubbles continue to come out, the procedure should be repeated several more times, but do not forget to monitor the volume of working material in the expansion tank.
- Then all you have to do is turn off the motor and remove the pipe from the valve head. Put the cap on the head itself, and then again diagnose the volume of liquid in the tank. If there is a need, it will need to be added. Further assembly of all components is carried out in reverse order.
Video “Assembling and adjusting the hydraulic system on a stand”
The process of assembling and adjusting the power steering using a special stand is presented in the video below (the author of the video is the Zavod Avtoagregatov channel).
Or power steering is simply a necessity for heavy and heavy vehicles. And if many people in passenger cars do without this assistant, then try turning the steering wheel of a Kamaz without it. Today we will learn everything about Kamaz power steering: the design of mechanisms, the principle of operation, and we will also talk about typical malfunctions and repairs.
Problems that the power steering solves
The main purpose of the amplifier is to minimize the effort required to turn the steering wheel when performing various maneuvers at low speeds.
The amplifier also makes the steering feel more noticeable at high speeds.
Device
What kind of power steering "Kamaz" has consists of a distributor, fluid, pump, as well as connectors and an electronic control unit.
The distributor is necessary to direct the flow of hydraulic fluids into the cavities of the system. A hydraulic cylinder solves the problem of converting hydraulic pressure into mechanical work of rods and pistons. The liquid not only transfers forces from the pump to the hydraulic cylinder, but also lubricates rubbing components and parts. Its pump is designed to constantly maintain the required pressure. It also promotes the circulation of fluids. The connector or tube of the KamAZ power steering is used to combine all the elements of this structure with each other. And finally, the electronic unit. It directs and regulates the operation of the amplifier.
The design of a typical power steering
What kind of power steering (Kamaz) device does it have? Often the actuators are presented in a single housing with the steering system. Such an amplifier can be called integrated. Various ATF type oils are used as hydraulic fluid. These are usually poured into FRGG.
How does he work? The Kamaz power steering system has a very simple operation scheme. When the steering wheel rotates, the rotary wheel, or one that is driven by the crankshaft belt, will begin to pump oil from the reservoir, and then will pump hydraulic fluid under sufficiently high pressure into the spool-type distributor. The latter monitors the force applied to the steering wheel and assists in turning the wheels. For this, a special tracking device is used. Often such an element in typical systems is a torsion bar. It is built into the section of the steering shafts.
If the car is stationary or moving in a straight path, then there is no force on the steering system shaft. Accordingly, the torsion bar is open and the distributor valves are closed. In this case, the oil is dumped into the tank. When the steering wheel is turned, the torsion bar tightens. The spool releases the channels, and the working fluid is directed to the actuator.
If the system is equipped with a rack and pinion mechanism, then the fluid is supplied directly to the rack housing. When the steering wheel is turned all the way, then safety valves come into play, releasing pressure in time and protecting mechanical components from possible damage.
Power steering "Kamaz-5320"
Its design is practically no different from a standard amplifier. There is also a distributor, a gearbox, as well as a hydraulic cylinder built into the steering wheel.
The operation of this unit is possible only with constant movement of the working fluid. This ensures low load on the pump. The system pressure is 8000 kPa. The power cylinder is integrated into the steering gear housing. A spool valve equipped with a system of reactive plungers and centering springs is used as a control valve. They create sensations of resistance forces at the moment the wheels turn.
Power steering "Kamaz-4310"
This unit here is almost completely the same as in model 5320. The principle of operation of the Kamaz-4310 power steering, the structure and design of this unit are practically no different. The main difference is only in the strengthening of some parts, as well as in the modified mounting of the steering bipod. Here the bolts, cotter pins and other fasteners have now been replaced with nuts and lock washers.
Hydraulic pump
The power steering pump is mounted in the camber of the cylinder block.
Kamaz trucks use a gear-type drive, but the pump is of the vane type. It has a double action. In one full revolution it performs two pumping and suction cycles.
Device
What type of device does the Kamaz power steering pump have? This unit consists of housing parts, a stator and a rotor, which is equipped with blades. The design also uses a shaft with bearings and a gear for drive. In addition to the pump, the design includes a distribution disc, as well as bypass and safety valves. There is also a tank, filter and manifold.
The housing parts, the stator, and the cover are connected and fastened with four bolts. The housing has a cavity where the sucked oil enters. At the end you can find two oval-shaped holes. They supply hydraulic fluid to the rotor. The cover has a special bore for the distribution disc, holes for the valves, and a channel. There is a hole in the bottom of the lid for calibration.
The rotor is mounted in the stator using splines. The blades are located in its grooves. The shaft can rotate using ball bearings. The liquid is directed to the blades using a distribution disc. Using a spring, the disk is pressed tightly against the stator and rotor. Then it limits the operation of the pump, and the safety element restrains the pressure that is created by the pump.
There is also a special tank for liquid. It is fixed to the pump housing. The tank has a special mesh filter. Here you can find a fill filter, as well as a safety valve.
How does the pump work?
When the rotor blades rotate, under the influence of inertia they are pressed against the stator. Liquid is supplied to the blades, which coincide with the holes in the housing, as well as the distribution disk. It is then pumped using blades into the narrower part between the rotor and stator. When the working cavities coincide with the holes in the disk, the liquid will exit through the holes behind the disk. And from there, under high pressure, it will go through the lower valve into the system. Oil from the cavity behind the disk enters the rotor blades and presses them even more tightly to the stator surface.
Injection and suction operate simultaneously in two places at once. When the rotor speed increases, the oil from the cavity behind the disc does not pass through the calibration hole. This increases the pressure and opens the bypass valve. A little liquid passes through the manifold back into the suction cavity. This reduces the performance of the mechanism.
About the most typical failures that are inherent in power steering
It must be said that Kamaz power steering malfunctions occur infrequently. With high-quality operation and timely maintenance of this unit, you can forget even about frequent adjustments. However, although infrequently, you can read about problems with the amplifier.
If it weren’t for the Russian winter, then the power steering would have worked the entire time the truck was in use. However, winter frosts and terrible roads often lead to too early wear of the power steering mechanisms. Typically, all breakdowns can be divided into mechanical problems and hydraulic faults.
Both mechanical and hydraulic problems can appear in any part of the assembly. Like any amplifier, it does not tolerate cold. He especially doesn't like too drastic changes. The same pump pumps out quite a lot of pressure. Consequently, if the viscosity of the working oil suddenly increases, the seals may be squeezed out.
In addition, it is not always possible to follow even the simplest rules of safe use. Drivers often leave their cars with their wheels turned out in extreme cold. After the engine is started, the pressure will increase on only one side. As a result, the seal will squeeze out. Also, few people replace hydraulic fluid according to regulations. And it can thicken over time. This leads to unnecessary pressure.
But this is winter, what about summer? But here problems arise mainly due to dust or dirt. Just a very slight depressurization of the system is enough, and soon the KamAZ power steering will need to be repaired. So, when depressurizing, the rods and bushings wear out. The former immediately rust and increase wear on the latter. After a couple of hundred kilometers, the gaps between the rod and bushing will become larger than permissible. So, the steering rack will knock.
Maintain cleanliness and fluid level
To avoid problems with the power steering, you need to keep it clean. Dirty hydraulic fluid can significantly accelerate the wear of the pump and seals in the steering rack mechanics of a truck.
You must try to monitor the oil level in the tank. If the level is lower, the pump will operate in premature wear mode.
Signs of typical element malfunctions
If you need to constantly level the car using the steering wheel while driving, then you need to check for free play in the steering wheel. If it is higher than necessary, the stroke should be adjusted. You also need to make sure and check whether the parts of the screw pair are worn out.
If air gets into the hydraulics, foamy and cloudy liquid can be seen in the reservoir. In this case, you need to flush and bleed the systems. The filter also needs to be replaced. In addition, one of the typical faults is the manifold gasket, which can wear out.
Repairs and adjustments
Repair work is reduced to replacing worn parts or assemblies. All spare parts for the amplifier are produced and are included in the assembly unit diagrams. Parts cannot be restored.
To make adjustments, you need to have a special tool - a dynamometer, and to check the pressure you will need a pressure gauge.
So, we found out what the Kamaz power steering system has, malfunctions, design and principle of operation.
It’s hard to imagine how the truck would handle if it weren’t for the KamAZ power steering system. The operation of the parts and mechanisms of this device has become familiar to a heavy unit. The unit helps the user apply minimal force to turn the steering wheel. In addition, a number of complex functions are performed that affect the safety of the machine.
Each mechanism is subject to wear and tear, which will lead to loss of performance. Hydraulic power steering is no exception; the condition of the unit affects other components of the engine. That is why timely maintenance is important to maintain the performance of the amplifier.
The weak link in the steering is the hydraulics. The entry of air bubbles into the channels of the mechanism can stall the work and create an emergency situation. In order to respond to an emergency situation in a timely manner, an experienced user knows how to upgrade the power steering on a KamAZ and restore functionality.
KamAZ-5350:
Purpose of the hydraulic power steering
The purpose of power steering is to reduce as much as possible the user's force applied to the steering wheel. In addition, the operation of KamAZ power steering affects stability when driving at low speeds. When moving quickly, in order to avoid an emergency, the amplifier creates additional resistance on the steering wheel. This stabilizes the ride along the road and keeps it on course.
The peculiarity of power steering on a car and other models is that if the mechanism breaks down or fails, control of the car is not lost, but remains in working order. The only drawback is that the user is forced to turn the steering wheel with greater force when turning the vehicle.
KamAZ power steering device
An amplifier is a set of parts and mechanisms combined into a closed system. The element bases are:
Directs streams of liquid (lubricant) into the nozzles, channels and cavities of the power steering.
- Volumetric hydraulic motor of reciprocating motion of a cylindrical shape.
The product converts the pressure generated by oil into the mechanical action of pistons and rods.
The working fluid, which is oil, is poured into the KamAZ power steering. The lubricant transmits force to the hydraulic cylinder from the pump. The material also prevents wear of surfaces, acting as a lubricant and sealant.
- Hydraulic power steering pump KamAZ-65115, etc.
The mechanism serves as a guarantor that maintains the level of constant pressure necessary for the normal functioning of the system. In addition, the pump constantly moves lubricant through the cavities and lines of the device.
Parts help connect and close parts, mechanisms, assemblies into one device.
The mechanism controls the operation of the system, analyzes and distributes efforts across work areas.
Power steering pump
The pump is considered the main device of the amplifier, since it creates pressure for the KamAZ power steering, without which operation is not possible. The mechanism is mounted in the area of the power plant frame. The pump is powered by a motor and is driven by a gear transmission. The creation of lubricant pressure in the system occurs due to the blades with which the pump is equipped. The unit performs 2 cycles of fluid intake and release per revolution of the steering wheel. You can also read about.
Principle of operation
By turning the wheels of KamAZ-5410 and others, the rotor blades perform rotational movements and are adjacent to the stator. The parts that coincide with each other form passages into which lubricant is supplied and passes further due to the resulting pressure. The formed pressure pushes the liquid through the lower valve due to the fact that the oil, at the moment the passages of the distribution disk and the surface coincide, goes beyond the products.
Power steering pump KamAZ-65116, etc.:
The oil enters the rotor blades, having previously passed through the distribution disk. Due to the pressure, the blades adhere more strongly to the stator. The inlet and injection of liquid occurs simultaneously in two directions. An increase in rotor speed prevents the passage of lubricant through a calibrated hole from the area located behind the disk. The resulting pressure acts on the bypass valve, forcing it to open. As a result of valve activation, part of the working fluid passes through the manifold and again enters the suction surface.
KamAZ power steering malfunctions
The advantage of the product is that KamAZ power steering malfunctions appear due to violations of operation and maintenance. Mechanism repair is a rare occurrence, but if breakdowns do occur, they occur at sub-zero temperatures.
Since the amplifier involves mechanics that interact between devices via hydraulics, faults are divided into:
- Mechanical type;
- Hydraulic type.
Replacing the KamAZ power steering oil seal:
Temperature changes negatively affect the hydraulics of the mechanism. Minus values make the working fluid thick, which increases the load on the oil seals and joint seals of the KamAZ-65222 vehicle, etc. The impact of increased pressure leads to oil leaks.
Violation of operating rules negatively affects the components and mechanisms of the amplifier. To extend the service life of the hydraulic booster, you need to take a competent approach to operation. So, leaving the car in the parking lot, the wheels of the vehicle are set to a level position. Otherwise, uneven load on the oil seal will lead to damage.
During the warm season, dirt and dust pose a danger. The penetration of abrasive particles into the mechanism of KamAZ and other models leads to increased friction and wear of the surfaces of parts. The impact entails depressurization of the system, wear of bushings, rods and other components.
Moisture seeps into the resulting gaps, causing rust on unprotected parts and causing increased wear. Operating the amplifier with similar problems leads to knocking in the steering rack, after which only replacing the KamAZ power steering will help. In order not to go to extremes, you need to tune the amplifier on time. The procedures performed are adjustment and pumping of the device.
Pumping the KamAZ hydraulic booster
If the mechanism has been repaired or filled with fluid, the next mandatory action is to pump the KamAZ power steering. The procedure is performed to eliminate air bubbles trapped inside the amplifier. If the air is not eliminated, the useful effect of the hydraulic control will drop sharply.
Power steering diagram of a KamAZ car:
Actions taken:
- Raise a car with a KamAZ-740 engine, or another model, so that the wheels of the car hang in the air. For this purpose, support the beams on supports.
Important!!!: If at least one wheel is on the surface, the procedure for bleeding the hydraulic power steering is not carried out.
- Dismantle the filler plug of the expansion tank neck; Remove the rubber pad from the exhaust valve. Install the rubber tube in the vacant space, dip the free edge of the product into a container with lubricant in an amount of about 1/2 liter;
- Unscrew the transfer valve one-half turn;
- Turn the steering wheel all the way to the left, pour lubricant into the expansion tank;
- Start the power plant and let it idle. At this time, with the engine running, pour lubricant into the conservator reservoir, without allowing the level to drop. Make sure that no air bubbles come out of the valve tube - close the valve;
- Alternately turn the steering wheel to the right and left. Make sure that the steering wheel remains stationary, unscrew the bypass valve 1/2 turn. Check to see if any air bubbles come out. When air does not flow, tighten the valve;
- Repeat the procedure, bleeding the power steering in a similar way as many times as required. A sign of the end of the process is the release of clean liquid from the free end of the hose without air impurities. If bubbles continue to come out, regulation is continued until the bubbles disappear completely;
- Turn off the power plant, remove the pipe, install the cap, diagnose the level of working fluid in the expansion tank, and add oil.
