Do-it-yourself KAMAZ chassis repair. Your attention

Since truck drivers often travel significant distances, they often have to do their own Kamaz repairs. Of course, in most cases we are not talking about a full-fledged repair - the driver cannot drag a trailer with spare parts behind him. However, the task of the driver is to correctly diagnose and take measures in order to safely return to the base or get to the car service.

However, the main way to prevent breakdowns is prevention. Moreover, for such a machine as Kamaz, repairs and maintenance are carried out in strict accordance with factory recommendations. The manufacturer provides for the initial period of operation of a new vehicle - a thousand kilometers. During this period, it is especially important to follow all the recommendations of the manufacturer, in particular, do not exceed the speed of fifty kilometers per hour and do not load the car by more than 75 percent of the nominal value. Moreover, a complete set of documents is attached to each new car, including a Kamaz repair manual.

Basic rules for driving a car. Frequent repairs

It is clear that the purpose of repair is, first of all, to prevent more serious breakdowns. Such preventive measures include the timely replacement of all working fluids. that lubricants and coolants must be selected in strict accordance with the existing recommendations of the car manufacturer.

Leaks in the cooling system, malfunctions of valves and tank gaskets must be eliminated without fail immediately after they are discovered. Otherwise, all this can lead to cavitation damage to the block and the liquid pump.

And, say, do-it-yourself Kamaz engine repair may be required if the pressure alarm in the lubrication system lights up. In this case, it is undesirable to continue the movement until the malfunction is found and eliminated. The use of a machine with a leaky intake tract can also lead to premature engine failure.

In order to avoid cracks in the cylinder head mounting bosses, it is necessary to securely isolate the threaded holes for the bolts from the ingress of dirt or liquid. It is especially important to carry out such insulation in the event that work is planned to replace engine heads.

Sometimes repairs may require welding. In this case, it is very important to control the disconnection of the battery. Also, the positive contact must be removed from the generator. As for the ground wire of the welding machine, it must be connected close to the weld.

As you know, repairs will be performed less often if the car is provided with proper operating conditions. However, there are recommendations on how to behave with a faulty car:

• If a coolant leak occurs while driving, the cooling system can be topped up with water. You should know that this measure is temporary. On such a coolant, you can get to the place of repair,
• if the machine is moved on roads with liquid mud, then it is necessary to periodically flush the surface of the radiator with water under pressure. This will avoid such a procedure as. In order to carry out such flushing, you need to raise the cab. Make sure that the jet of water does not hit the generator,
• towing a car with an idle engine must necessarily include an operation to remove the cardan shaft. This will help delay the repair of the Kamaz gearbox, because otherwise you will be provided with scuffing of the bearings of the gears of the output shaft in the gearbox.

Maintenance intervals

As already mentioned, the importance of preventive examinations cannot be underestimated. Indeed, thanks to this, you can avoid such manipulations as, and you can insure yourself against unpleasant breakdowns while driving.

You need to perform a daily inspection of the main parts and assemblies. This inspection includes checking the level of working fluids, as well as several other manipulations:

• checking the condition of the steering drive,
• checking the operation of all brake systems,
• checking the condition of wheels and tires.

In order to ensure the trouble-free operation of all nodes, scheduled inspections are carried out. Their frequency is twice a year. Such inspections are called seasonal maintenance and are designed to prepare the car for operation, respectively, in winter and summer.

TRANSMISSION

The transmission of a car is a set of units and mechanisms designed to transmit torque from the engine to the drive wheels and change it in magnitude and direction. The transmission (Fig. 1.1) of the KamAZ vehicle is mechanical and consists of a clutch, gearbox, transfer case, cardan drive, main gears, differentials, axle shafts

Rice. 1.1. Transmission layout:

1-clutch; 2-gearbox; 3-distributing box; 4-cardan transmission; 5- main gear and differential; 6-axle

CLUTCH Clutch is designed to: ü disconnect the engine from the transmission when shifting gears, hard braking; ü smooth connection of the engine with the transmission when starting off; ü protection of the engine and transmission from overloads; transmission of torque from the engine to the gearbox. By type, the clutch is dry, double-disk, constantly on, with a peripheral arrangement of pressure springs. It is located in the crankcase, mounted on the engine, and consists of a clutch mechanism and a control drive.

1.1. CLUTCH MECHANISM

It consists (Fig. 1.2) of the leading parts, driven parts, pressure device, shutdown mechanism. The principle of operation of the clutch is based on the use of frictional forces that occur between the discs. The clutch drive discs receive engine torque from the flywheel, and the driven discs transmit this engine torque to the gearbox input shaft. The pressure device (12 pressure springs) provides a tight pressing of the driving and driven parts of the clutch to create the required friction torque. The torque from the driving parts is transmitted to the driven parts due to friction forces.

Rice. 1.2. Clutch Mechanism: 1 - driven disk; 2- leading disk; 3- mounting sleeve; 4- pressure plate; 5-fork of the retractable lever; 6 - retractable lever: 7 - thrust ring spring; 8-hose coupling lubrication; 9-loop spring; 10 release bearing; 11-pull spring; 12 clutch release clutch; 13- clutch release fork; 14 - thrust ring; 15- fork shaft; 16- pressure spring; 17- casing; 18-heat-insulating washer; 19- casing mounting bolt; 20- clutch housing; 21 flywheel; 22-friction bookmark; 23- primary shaft; 24 - torsional vibration damper disk; 25- spring damper torsional vibrations; 26-ring of the driven disk; 27-mechanism for automatic adjustment of the position of the middle driving disk K leading details include the middle drive plate, pressure plate, clutch cover.

The middle driving disk (Fig. 1.3, a) is cast from cast iron and installed in the grooves of the flywheel on four spikes evenly spaced around the circumference of the disk. To ensure clutch ventilation, better heat dissipation and weight reduction, windows are made in the disc body, separated by internal ribs. The spikes house a lever mechanism that mechanically adjusts the position of the middle disc when the clutch is disengaged to ensure clean disengagement. The pressure plate (Fig. 1.3, b) is cast from gray cast iron, like the middle drive plate, it is installed in the grooves of the flywheel on four spikes. On the one hand, the disk has a polished surface, on the other - 12 bosses for installing pressure springs.

Rice. 1.3. Clutch discs: a - the middle drive disk; b - pressure plate; c - driven disk with damper assembly: 1-hub; 2-rivet; 3-clip damper; 4-slave drive; 5-friction lining; 6 - damper spring Each spike on the side of the casing has a tide in which a groove is milled and two holes are bored to install the axle of the clutch release lever. The clutch cover is steel, stamped, mounted on the flywheel housing on two mounting sleeves and fastened with 12 bolts. The casing has 12 recesses for installing springs and holes for installing lever forks.

TO driven parts include two driven discs with a damper, a clutch driven shaft (aka the input shaft of the gearbox). The driven disk (Fig. 1.3, c) consists of a disk with friction linings, a disk hub, a damper (torsional vibration damper). The driven disk is made of steel. In the center of the disk there is a hole for installing the hub. The disc has eight windows for the damper springs. Along the periphery of the disk, friction linings made of asbestos composition are riveted on both sides. The hub has internal splines that are mounted on the splines of the input shaft of the gearbox. The hub also has eight windows for damper springs. The damper serves to dampen the torsional vibrations that occur in the engine and transmission. Due to the uneven operation of the engine and the elasticity of the crankshaft, there is a constant twisting and unwinding of the shaft, i.e. natural torsional vibrations occur. The transmission contains shafts of the gearbox, transfer case, cardan drive, axle shafts.

With a sharp engagement of the clutch, braking of the car without disengaging the clutch, when the wheels hit an obstacle, forced oscillations occur in the transmission shafts. When the engine runs unevenly, torsional vibrations from the engine can be transmitted to the transmission. This is especially dangerous when the frequency of natural angular vibrations of the transmission coincides with the frequency of torsional vibrations. In this case, resonance sets in and the load on the transmission parts increases dramatically, which can lead to their breakdown. Forced torsional vibrations in the transmission, in turn, can be transmitted to the engine, which dramatically increases the load on its parts. Therefore, to protect against resonant torsional vibrations of the shafts, dampers (torsional vibration dampers) are installed in the clutch discs. The damper has elastic and friction elements.

The elastic element serves to change the vibration frequency of the shafts and prevent the resonance phenomenon, i.e. coincidence of the frequencies of natural angular vibrations and torsional vibrations, and consists of eight cylindrical springs. The friction element reduces the amplitude of forced oscillations, converting the energy of oscillations into heat, and consists of two clips, two disks, two friction rings. Damper discs and clips are riveted to the hub flange on both sides. Friction rings are riveted to the driven disk on both sides. The friction rings and damper discs also have eight windows, the windows for the springs coincide with the windows in the driven disk and the hub flange. Eight cylindrical springs are installed in the windows.

Thus, there is no rigid connection between the driven disk and its hub - they are connected only through eight springs. The damper discs are made in the form of Belleville springs and are constantly pressed against the friction rings. When torsional vibrations occur, the hub of the driven disk rotates relative to the disk itself; the damper springs, being compressed, change the oscillation frequency, providing a mismatch between the frequencies of the natural vibrations of the transmission and forced torsional vibrations, i.e., they prevent the phenomenon of resonance. When the hub is turned, the damper discs slide along the friction rings, and due to friction, the vibrational energy is converted into heat.

Pressure device(see fig. 1.2) consists of twelve springs. The springs rest on the bosses of the pressure plate through washers made of thermally insulating material. The total force of the springs is 10500...12200N (1050...1220 kgf).

Shutdown mechanism consists of four release levers, a thrust ring, a clutch release clutch with a release bearing, a clutch release fork with a shaft, two release springs. Four pull levers are mounted on the pressure plate and connected to the casing with forks. Pull levers are connected to the pressure plate and fork fingers. The pins are mounted in the disk and forks on needle bearings. On the axis of the lever in the fork, a thrust ring spring is installed, which with one antenna rests against the casing, and with the other, through the loop, constantly presses the thrust ring against the release levers. The thrust ring protects the release levers from wear. To disengage the clutch, a clutch release clutch with a bearing assembly is installed on the cover of the input shaft of the gearbox. The clutch, under the action of the springs, is constantly pressed by the crackers pressed into it against the paws of the clutch release fork. To lubricate the clutch and bearing, a lubricant supply hose and an oiler are installed on the clutch housing. The clutch release fork is mounted on the drive shaft, which, in turn, is mounted on bushings in the bores of the clutch housing. The fork shaft lever is mounted on the outer end of the shaft.

1.2. CLUTCH CONTROL ACTUATOR The drive is remote, hydraulic, with pneumatic booster, designed to disengage the clutch. The capacity of its hydraulic system is 0.38 liters. The fluid used is GTZh-22M or "Neva", "Tom". It consists (Fig. 1.4) of a clutch pedal with a retractable spring, a master cylinder, a pneumohydraulic booster, a clutch release fork shaft lever with a retractable spring, a pusher, and pipelines.

Rice. 1.4. Clutch drive: 1-pedal; 2- bottom stop; 3-bracket; 4- top stop; 5- lever; 6-finger eccentric; 7- piston pusher; 8- pull-back spring; 9- main cylinder; 10-hydraulic pipeline; 11-pneumohydraulic amplifier; /2-cork; 13-bypass valve; 14-pneumatic pipeline; 15-protective cover; 16- piston pusher; 17-spherical adjusting nut; 18-compensation tank; a - compressed air

When you press the pedal when the clutch is disengaged, the force from the driver's foot through the lever and the rod is transmitted to the main cylinder, from where the liquid under pressure through the pipeline enters the body of the follower, which at the same time ensures the passage of compressed air coming through the air pipeline through the pressure reducing valve from the air cylinder. At the same time, pressurized fluid from the main cylinder enters the booster hydraulic cylinder. The total force of the air pressure in the pneumatic booster cylinder and the fluid pressure in the hydraulic cylinder is transferred to the pneumatic booster rod.

The rod moves the lever of the clutch fork shaft, which, turning, disengages the clutch. clutch pedal installed on the axis of the bracket. It transmits force to the master cylinder piston pusher by means of a lever and an eccentric pin. master cylinder(Fig. 1.5) is mounted on the clutch pedal bracket.

Rice. 1.5. Master cylinder: 1-pusher (rod) piston; 2-body; 3-piston; 4-tank body; 5-free play clearance of the master cylinder; A - free play clearance of the master cylinder Consists of a cylinder body, a protective cover, a rod, a piston, an end sealing cuff, a spring, a cylinder plug, a tank body.

In the body of the main cylinder, two cavities are formed, separated by a partition. The upper cavity, together with the tank, is designed for filling the hydraulic drive with working fluid and storing the necessary supply of working fluid. The lower cavity serves as the working cavity of the main cylinder, in which a piston with a cuff and a spring is installed. The pneumatic-hydraulic booster of the clutch drive is used to create additional force in order to facilitate clutch control. It is attached with two bolts to the clutch housing flange on the right side.

The amplifier (Fig. 1.6) consists of the front 35 and rear 44 cases, the clutch release piston 43 with the pusher 3, the pneumatic piston 31, the follower.

Rice. 1.6. Pneumohydraulic booster of the clutch drive: a- brake fluid supply; b-air supply; 1-spherical nut; 2-locknut; 3-pusher of the clutch release piston; 4-protective cover; 5-ring; 6-piston seal housing; 7-sealing ring; 8-cuffs of the follower piston; 9-following piston; 10-case of the follower piston; 11-bypass valve; 12-cap; 13-outlet seal; 14-outlet cover; 15-screw fixing the cover; 16-diaphragm of the tracking device; 17-diaphragm seat; 18-sealing ring; 19-diaphragm spring; 20-cork; 21-return spring; 22-inlet valve seat; 23-inlet valve; 24-valve stem; 25-air supply cover; 26 outlet valve; 27-adjusting shims; 28-nut; 29-diaphragm washer; 30-thrust ring; 31-pneumatic piston; 32-gasket; 33-cork; 34-piston cuff; 35-front case; 36-piston spring; 37 washer; 38-seal cuff; 39-spacer sleeve; 40 spacer spring; 41-thrust sleeve; 42-piston cuff; 43clutch release piston; 44-back housing The front housing is cast aluminum alloy. It has a hole (above) and a drill (below).

The drilling is designed to install the pneumatic piston. The upper stepped hole is designed to install an inlet valve with a follower seat. The valve cavities in the upper hole and the over-piston space of the lower drilling are interconnected by a channel. There is a plug 33 in the housing wall to remove condensate. In the cylinder of the front housing there is a pneumatic piston 31 with a cuff and a return spring. The piston is pressed onto the pusher, which is integral with the hydraulic piston.

The hydraulic piston pusher has a spherical nut 1 and a lock nut 2. The forces from the pneumatic and hydraulic working pistons are summed up and transmitted through the pusher and its spherical nut to the clutch release fork shaft lever. A hole (bottom) and drilling (top) are bored in the rear cast-iron body 44. The hole acts as a cylinder for the hydraulic clutch release piston. From the side of the front housing, the piston seal is installed and fixed in the hole. The top drilling is designed to install the follower piston housing. The working fluid from the main cylinder enters the cavity of the hydraulic piston through the hole a in the housing.

Compressed air is supplied to the upper cavity of the front housing through an opening in the housing cover. The tracking device is designed to automatically change the air pressure in the power pneumatic cylinder behind the piston in proportion to the force on the clutch pedal. It consists of a follower piston with a cuff 8, a follower piston housing 10, a diaphragm with an exhaust valve seat and a spring, an exhaust and intake valves with a return spring. A follower piston with a cuff is installed in the housing. The piston stroke is limited by the thrust ring. The diaphragm is sandwiched between the housings; in it, with the help of a nut, the exhaust valve seat and two plates of the diaphragm spring are fixed. The conical exhaust and intake valves are assembled on a common stem. The valve spring presses the inlet valve against the seat fixed in the body with the air supply cover.

Channel b for supplying compressed air to the pneumatic piston cylinder is connected to the cavity in front of the diaphragm by a calibrated hole. The air from the pneumatic piston cylinder is released through the exhaust valve, the internal cavity of the exhaust valve seat and the hole closed by a seal with a cover.

Chapter II. CLUTCH OPERATION AND MAINTENANCE

CLUTCH OPERATION Initial position.

The clutch pedal is in its original position, the master cylinder rod is in the upper position. The piston, under the action of a spring, is pressed against the bulkhead of the housing. There is a gap between the rod and the piston, the cavities of the main cylinder communicate with each other. There is no pressure in the pipeline connecting the master cylinder to the hydraulic booster. The pusher of the hydraulic piston of the hydraulic booster, under the action of the return spring of the fork shaft lever, is pressed against the hydraulic piston, which, through another pusher, holds the pneumatic piston in its original position. The pressure plate 4 (see Fig. 1.2) of the clutch under the action of pressure springs 16 presses the driven discs to the middle drive disc 2 and the flywheel 21. The clutch release clutch under the action of the springs is removed from the thrust ring 14 by 3.2 ... the most complete engagement of the clutch.

The torque developed by the engine is transmitted from the crankshaft to the flywheel, the middle drive and pressure plates, and then, due to friction, to the driven discs. From the driven disks, the torque is transmitted through the damper to the hubs of the driven disks and then to the input shaft 23 of the gearbox.

Clutch disengagement. When the clutch pedal is pressed, the pusher 1 of the main cylinder (see Fig. 1.5) closes the hole in the piston 3, preventing fluid from flowing from the lower cavity to the upper one, and moves the piston, compressing the spring. When the piston moves in the cylinder, the pressure increases, which is transmitted through hoses and pipelines to the inlet of the pneumatic hydraulic booster. The working fluid under pressure enters the cylinder cavity of the hydraulic piston of the amplifier (Fig. 1.6) and then through the channel in the rear housing is supplied to the follower piston 9. The follower piston begins to move, while compressing the diaphragm spring and moving the exhaust valve seat. The seat, moving, closes the exhaust valve, while compressing the valve spring, and opens the intake valve. Compressed air enters the over-piston space of the pneumatic piston 31.

The piston begins to move, compressing the spring, and moves the hydraulic piston through the pusher, and through its pusher 3 it turns the shaft lever 15 of the fork 13 (see Fig. 1.2), which, in turn, turns the shaft and the clutch release fork associated with it. The fork with its paws presses the crackers of the clutch release clutch, moves it, choosing the gap, until it stops against the thrust ring of 14 levers. With further movement of the clutch, the thrust ring presses the pull levers 6, rotates them on the axes of the forks and presses the pressure disk 4 from the driven disk, while compressing the pressure springs 16. The levers of the middle drive disk 27 turn under the action of their springs and move the disk to the middle position.

The torque developed by the engine is not transmitted to the driven disks and further to the transmission. Part of the compressed air through the calibrated holes in the front housing is supplied to the diaphragm cavity. The follower piston is under the action of two forces directed towards each other. When the clutch pedal is fully depressed, the fluid pressure on the follower piston is maximum, so the inlet valve is fully open and the pneumatic piston under compressed air pressure takes the left position, ensuring complete disengagement of the clutch.

Clutch engagement. When released, the clutch pedal returns to its original position under the action of the release spring, and the master cylinder piston also returns to its original position under the action of fluid pressure. The fluid pressure on the booster follower piston decreases, the follower piston moves to the left position, the diaphragm bends under the action of the spring and compressed air pressure, moving the exhaust valve seat. The inlet valve, under the action of a spring, sits on the saddle, stopping the supply of compressed air. The exhaust valve, with further movement of the seat, breaks away from it and communicates the over-piston space of the pneumatic piston cylinder with the atmosphere.

The piston under the action of the spring moves to the right position. The hydraulic piston, first under the action of the clutch pressure springs, and then under the action of the return spring of the lever of the clutch fork shaft, takes its original position. The clutch release clutch with the bearing ceases to act on the thrust ring of the pull levers. At the same time, the pressure plate, under the action of pressure springs, presses the driven discs against the flywheel and the middle drive disc, the pressing force increases gradually, due to the follow-up action of the pneumatic booster. The torque transmitted to the input shaft of the gearbox from the engine gradually increases and reaches its maximum value.

To fully disengage the clutch, the driver must apply a pedal force of 150N (15kgf). In the absence of compressed air in the pneumatic system of the car, the clutch can be disengaged due to pressure only in the hydraulic part of the booster. At the same time, to create the necessary pressure, the driver must increase the force on the clutch pedal to 600N (60kgf).

On the follower piston The amplifier has two forces. One force from fluid pressure on the piston, which tends to move the piston and open the intake valve. The other is from the action of the diaphragm spring and the pressure of compressed air on the diaphragm; it tends to close the intake valve. If the driver does not press the clutch pedal all the way and stops it in an intermediate position, then with an increase in pressure in the diaphragm cavity, there comes a moment when the force of the compressed air and the spring on the diaphragm becomes greater than the fluid pressure force on the follower piston. In this case, the diaphragm will move to the left so that the return spring closes the intake valve. As the follower piston moves, the fluid pressure increases and the forces on both sides of the follower piston are balanced. In this case, both valves (inlet and outlet) are closed and the follower piston is in an intermediate position.

With an increase in the pressure of the working fluid (i.e., with further movement of the clutch pedal), the inlet valve will open and a new portion of air will enter the air piston cylinder, which will ensure the movement of the piston and further disengagement of the clutch. The follow-up action of the pneumatic booster ensures smooth engagement of the clutch.

CLUTCH MAINTENANCE

During the operation of the clutch, the friction surfaces wear out, the control drive is coupled, the amplifier loses its tightness, which leads to a violation of the adjustment parameters. Lubricant is also consumed. The intensity of these processes depends mainly on road conditions, the load in the body on the hook, the number of vehicles on the roads, as well as the practical skills of drivers. Therefore, during the operation of cars, maintenance of the clutch is provided.

During maintenance: ü check the tightness of the drive, the integrity of the release springs of the clutch pedal and the lever of the clutch release fork shaft; ü adjust the free play of the pusher of the piston of the main cylinder of the drive and the free play of the lever of the shaft of the clutch release fork; ü lubricate the bearings of the clutch release clutch and the shaft of the clutch release fork; ü check the fluid level in the clutch master cylinder reservoir, add fluid if necessary; ü tighten the pneumatic booster mounting bolts; ü change the fluid in the clutch hydraulic system (once a year in autumn). During operation, as the lining of the driven disks wears out, it is necessary to adjust the clutch actuator to ensure free play of the clutch release clutch.

Clutch control consists in checking and adjusting the free play of the clutch pedal, the free play of the clutch release clutch and the full stroke of the pneumatic booster pusher.

Clutch free play disengagement of the clutch is checked by manually moving the lever of the fork shaft. At the same time, disconnect the spring from the lever. If the free play of the lever, measured at a radius of 90 mm, turns out to be less than 3 mm, adjust it with a spherical nut of the pusher to a value of 3.7 ... 4.6 mm, which corresponds to a free play of the clutch release clutch of 3.2 ... 4 mm. The full stroke of the pneumatic booster pusher must be at least 25mm. Check the full stroke of the pneumatic booster pusher by pressing the clutch pedal to the stop. With a smaller stroke, the clutch is not fully disengaged. In case of insufficient stroke of the pneumatic booster pusher, check the free play of the clutch pedal, the amount of fluid in the clutch master cylinder reservoir, and, if necessary, bleed the clutch hydraulic system.

Pedal free play, corresponding to the beginning of the operation of the main cylinder, should be 6 ... 15 mm. It is necessary to measure it in the middle part of the clutch pedal platform. If the free play goes beyond the limits indicated above, adjust the gap A (see Fig. 1.5) between the piston and the master cylinder piston pusher with the eccentric pin 6 (see Fig. 1.4), which connects the upper eye of the pusher 7 with the lever 5 of the pedal. Adjust the gap when the release spring 8 presses the clutch pedal against the upper stop 4. Turn the eccentric pin so that the pedal travel from the upper stop until the plunger touches the piston is 6.15 mm, then tighten and cotter the castle nut. The full travel of the clutch pedal should be 185...195mm.

Hydraulic system bleeding to remove air pockets that occur due to a violation of the tightness of the hydraulic drive, in the following order: tank filler neck. Fill the system with working fluid, using a strainer to prevent foreign impurities from entering the system; ü remove cap 12 from the bypass valve on the pneumatic booster (see Fig. 1.6) and put a hose on the valve head to bleed the hydraulic drive.

Lower the free end of the hose into a glass vessel with a capacity of 0.5 l, filled with working fluid to 1/4 ... 1/3 of the height of the vessel; ü unscrew the bypass valve by 1/2 ... 1 turn and sequentially sharply press the clutch pedal until it stops at the stroke limiter with intervals between pressing 0.5 ... 1 s until air bubbles stop emitting from the working fluid entering the glass vessel; ü when pumping, add working fluid to the system, preventing its level in the tank from dropping below 40 mm from the upper edge of the tank filler neck to prevent air from entering the system; ü at the end of pumping, with the clutch pedal pressed all the way, turn the bypass valve to failure, remove the hose from the valve head, put on the cap; ü after pumping the system, add fresh working fluid to the tank to the normal level (15...20 mm from the upper edge of the tank filler neck). The quality of pumping is determined by the value of the full stroke of the pneumatic booster pusher. To check the fluid level during operation, open the filler cap of the tank. In this case, the liquid level must be at least 15 ... 20 mm from the upper edge of the filler neck.

Chapter III. POSSIBLE FAULTS IN THE CLUTCH AND METHODS FOR THEIR ELIMINATION

There may be the following main malfunctions in the clutch: violation of the drive adjustment, causing incomplete disengagement and uneven engagement of the clutch, slipping of the discs; wear of the friction linings of the driven disk, the clutch release clutch bearing, the cuff of the clutch slave cylinder.

Clutch slip occurs when the pressure springs are weakened or broken, the friction surfaces of the flywheel and pressure plate are worn or warped, the friction linings of the driven disk are oiled. Defective pressure springs and oily friction linings are replaced with new ones. The friction surfaces of the flywheel and pressure plate are processed by grinding.

Incomplete clutch disengagement appears as a result of increased pedal free play (with a mechanical drive) or a decrease in the piston stroke of the working cylinder (with a hydraulic drive), as well as due to deformation of the driven disk. The pedal free play is set during adjustment, and the defective driven disk is replaced with a new one.

Unsmooth clutch engagement due to wear of the lining of the driven disk, difficult movement of the hub of the driven disk, non-simultaneous pressing of the release bearing, jamming of the clutch pedal on the axle. The difficult movement of the hub of the driven disk on the splines of the input shaft of the gearbox occurs due to the presence of nicks or burrs on the splines. The latter are cleaned and lubricated with a thin layer of graphite grease. The inconsistency in pressing the clutch release bearing on the release levers is eliminated by adjustment. When the clutch pedal seizes, clean the ends of the bushings from nicks and burrs and lubricate them. When repairing, worn clutch release bearings are replaced with new ones. Driven and pressure disks, as well as pressure springs, depending on the condition, are subjected to restoration or replacement. To perform repair work, the clutch is disassembled using devices, one of which is shown in Fig. 3.1.

Rice. 3.1. Clutch disassembly and assembly tool: 1 - base plate, 2 - clamping body, 3 - control ring, 4 - mounting studs, 5 - base

clutch housing and the cylinder block is not depersonalized during repair. They are marked to prevent dismantling and ensure alignment of the engine crankshaft and the gearbox input shaft. If these parts are impersonal, then after assembly, the centering hole of the clutch housing is bored in the fixture. The main defects of the clutch housings are cracks, chips, thread breakage or wear, wear of the holes and bearing surfaces of the paws attached to the frame. Crankcases are rejected if cracks cover more than half of the perimeter or pass through more than one hole for mounting bolts. Cracks in the clutch housing are welded. Chips capturing the hole weld or weld the chipped part of the part.

If the thread is broken up to two threads, it is restored by running with a tap. If the thread has a breakdown of more than two threads or is worn out, then it is restored by cutting a thread of an increased repair size, setting a screw driver or welding, followed by cutting a thread of a nominal size. Worn out holes for the guide pin of the starter mount, the engine mounts to the frame, which are more than the limit size, are restored by setting an additional part - the bushing. After pressing, the bushings are machined to the nominal size. The worn bearing planes of the paws for fastening the clutch housing to the frame are processed on a milling machine until the signs of wear are eliminated. With significant wear, washers are welded.

Before welding, the paw surface is milled, and the holes are countersinked to install washers. The washers are then welded to the clutch housing with a solid seam by electric arc welding. Finish processing by countersinking the ends of the paws flush with the base metal. Major defects pressure and driven discs clutch are cracks on the surface of the pressure plate or friction linings of the driven disk, wear of the friction linings, warping or curvature of the disk, loosening of the rivets fastening the linings or hub, wear and tear of the working surfaces of the pressure and middle disks. Discs and friction linings with cracks are rejected. Worn friction linings are replaced with new ones. To do this, remove the old rivets.

The driven disk is corrected, having previously cleaned the nicks and burrs on the hub. Warping is set on the calibration plate using a feeler gauge. A probe 0.3 mm thick should not pass between the end surface of the disc and the plate. Friction linings are riveted under pressure using a stamp. Instead of rivets, glue is also used to connect the friction linings to the disc. The warping of the plane of contact of the pressure plate with the driven disc is not more than 0.15 mm or the curvature of the driven disc is greater than the value specified in the technical specifications, is eliminated by editing. The pressure plate is corrected on the press, installing on the ring located on the press table, with the plane of contact to the driven disk down. Editing of the driven disk is carried out on a plate or in a fixture using a special mandrel. Linings are rejected if the rivets fastening them to the driven disks are loosened.

When loosening more than four rivets fastening the hub of the driven disk, the rivets are replaced. To do this, worn holes in the hub and disk are drilled to an increased repair size or new holes are drilled between the existing ones. The repaired driven disc assembly with pads must be balanced. Permissible imbalance is established by the technical specifications. Wear and tear of the working surface of the pressure and middle discs is eliminated by processing on a grinding or turning machine. In this case, the minimum thickness of the disk must be at least the value specified in the technical specifications. After assembling the clutch, install it on the engine and check its operation in the off and on positions.

For ensure free travel of the clutch disengagement of the clutch as the pads of the driven discs wear out, it becomes necessary to adjust the clutch drive. The clutch engagement drive for KamAZ vehicles is hydraulic. Adjusting the drive of the KamAZ clutch release mechanism consists in checking and adjusting the free play of the clutch pedal, the free play of the clutch release clutch and the full stroke of the pneumatic booster pusher. To determine the free play of the clutch, the lever of the clutch fork shaft is moved from the spherical surface of the nut 18 of the pusher 17 (see Fig. 3.2, a) of the pneumatic booster when the clutch release spring is disconnected from the lever.

If the free travel of the clutch release lever, measured at a radius of 90 mm, is less than 3 mm, then it is adjusted with nut 18 to a value of 3.7 ... 4.6 mm. This corresponds to a free play of the clutch release of 3.2...4m. Clutch pedal free play KAMAZ vehicles are measured in the middle part of the clutch pedal platform 1 (Fig. 3.2, a). It should be 6 ... 12mm. The free play is regulated by changing the gap between the piston and the master cylinder piston pusher 9 with an eccentric pin 6 connecting the upper eye of the pusher 7 with the pedal lever 5. The operation is performed with the clutch pedal pressed against the upper stop 4 by the withdrawal spring 8. By rotating the eccentric pin, the required movement of the pedal is achieved from the upper stop until the pusher touches the piston. Then tighten and cotter the nut.

Rice. 3.2. Clutch Release Drive: a - hydraulic KamAZ vehicles; b - mechanical ZIL cars: 1-clutch pedal; 2-bottom stop: 3-bracket; 4-top stop; 5-lever; 6-eccentric finger; 7-piston pusher; 8 and 23-pull springs; 9-master cylinder; 10- hydraulic line (hose); 11-front housing of the pneumatic booster; 12-rear housing of the pneumatic booster; 13-cork; 14-bypass valve; 15-pneumoline; 16-protective cover; 17- pneumatic booster piston pusher; 18-spherical adjusting nut; 19-reducing valve; 20-thrust fork with a spring; 21-adjusting nut; 22-fork lever; 24-clutch release fork; 25-clutch release with release bearing; 26-return spring

When adjusting the free play of the clutch pedal with a mechanical drive (Fig. 3.2, b), unscrew the lock nut of the nut 21 by a few turns, rotate the nut 21, changing the length of the rod 20. To increase the free play, the nuts 21 are unscrewed, and to reduce, they are wrapped. After adjustment, while holding the nut 21 motionless, tighten the lock nut until it stops.

Full stroke of the pneumatic booster pusher check after pressing the clutch pedal to the stop. For KamAZ vehicles, it must be at least 25mm. With a smaller stroke, the clutch is not fully disengaged. If the pusher of the pneumatic booster does not move enough, check the free play of the clutch pedal, the volume of fluid in the clutch master cylinder and, if necessary, pump the hydraulic system of the clutch drive.

Liquid level "Neva" in the tank of the master cylinder of the clutch release mechanism drive KamAZ vehicles are checked using a probe from the driver's tool kit. The normal fluid level in the hydraulic cylinder corresponds to 40 mm of the length of the wetted surface of the probe, the permissible one is 10 mm. The total volume of fluid in the hydraulic clutch is 280 cm 3. Once every three years in the fall, the fluid in the clutch hydraulic drive system is replaced.

Bleeding the clutch hydraulic system KAMAZ vehicles are performed after the leak in the hydraulic drive has been eliminated in the following sequence: 1) the rubber protective cap of the bypass valve 14 is cleaned of dust and dirt (see Fig. 3.2, a) and removed. Put on the valve head rubber hose attached to the car. The free end of the hose is placed in a glass vessel with brake fluid; 2) sharply press the clutch pedal 3-4 times. With the pedal depressed, the air release valve is unscrewed by 0.5-1 turn.

Part of the liquid and the air contained in it in the form of bubbles will come out through the hose; 3) after the fluid outlet stops with the clutch pedal depressed, turn on the bypass valve; 4) steps 2 and 3 are repeated until the release of air from the hydraulic system through the hose completely stops. Fluid is periodically added to the system to prevent air from entering the system while it is being pumped. Its level in the compensation cavity of the main cylinder should not decrease by more than 2/3 of the height from the normal level mark; 5) at the end of pumping, with the pedal depressed, completely wrap the bypass valve, remove the hose from its head and install a protective cap on the valve head; 6) add fluid to the master cylinder to a normal level. The quality of pumping is determined by the full stroke of the pusher of the pneumatic booster of the clutch drive.

Control and drainage of condensate in the hydraulic cylinder of the pneumatic booster of KamAZ vehicles, it is carried out after unscrewing the plug 13 (see Fig. 3.2, a) in the front housing of the pneumatic booster. To completely remove condensate, the cylinder is purged by lightly pressing the clutch pedal.

Clutch lubrication and hydraulic system flush drive consider the example of the clutch of KamAZ cars. The clutch release shaft bushings are lubricated through two grease fittings 3 (Fig. 3.3), and the clutch release clutch bearing is lubricated through a grease fitting 2 with a syringe. To prevent lubricant from entering the clutch housing, the number of strokes with a syringe should not exceed three.

Rice. 3.3. Lubrication points for clutch and gearbox with a divider for KamAZ vehicles: 1 breather; 2-press grease fitting release bearing; 3-press grease fitting; 4 and 5 drain plugs with magnet; 6-filler plug with level indicator; 7-drain plug Flush the hydraulic system of the clutch drive with technical alcohol or clean brake fluid at least once every three years. At the same time, the main cylinder and the pneumatic booster are completely disassembled. Pipelines after washing are blown with compressed air, having previously disconnected them from both ends. Hardened, worn or damaged working edges of the cuffs are replaced with new ones. Before assembly, the pistons and cuffs are lubricated with brake fluid. After filling the hydraulic system of the clutch drive with fresh brake fluid, it is pumped to remove the air that has appeared.

To replace the pneumatic clutch hydraulic booster KamAZ vehicles, you must do the following: release air from the pneumatic drive of the brake system through the valve on the air cylinder; remove the release spring 8 (see Fig. 3.2) of the lever 5 of the clutch release fork shaft; disconnect the pneumatic line 15 of the pneumatic booster and the hydraulic line 10; drain the fluid from the hydraulic drive system; unscrew the two bolts of the pneumatic booster and remove it together with the pusher 17. Install the pneumatic booster in the following sequence: fix the booster on the clutch housing (divider) with two bolts with spring washers; attach the hydraulic line 10 of the pneumatic booster and the pneumatic line 15;

install the release spring 8 of the clutch release fork shaft; pour brake fluid into the compensation cavity of the master cylinder through the upper hole with the protective cover removed; bleed the hydraulic drive system; check the tightness of the pipeline connection; eliminate leakage of brake fluid by tightening or replacing individual parts; check and, if necessary, adjust the gap between the end face of the cover and the stroke limiter of the gear divider engagement rod. Table 1

Clutch malfunctions

Malfunction	sign malfunctions	Cause malfunctions	Remedy
Clutch slips (incomplete engagement)	The vehicle picks up speed slowly or loses speed slowly on a hill. There is a specific smell of burning linings in the cab	There is no clearance between the thrust ring and the release bearing (there is no free play in the clutch) Lubrication on the friction surface Friction lining wear Breakage or loss of elasticity of pressure springs	Adjust clearance 3.2.4mm (clutch free play) Remove the clutch and wash the friction surfaces Replace friction linings Replace compression springs
Clutch "leads" (partial disengagement)	Engaging gears is accompanied by a rattle The force on the lever increases sharply when shifting gears	Large clearance between thrust ring and release bearing Warping of the driven disks or destruction and breakage of the linings Air in the hydraulic actuator or fluid leakage	Gap adjust Discs replace Add liquid, eliminate the leak, remove air from the hydraulic system (“pump” the system)
Increased force on the clutch pedal	When you press the pedal, the resistance increases.	Compressed air does not enter the pneumatic booster (pneumatic booster does not work) Hardening of the follower piston	Replace valve Replace follower piston seal or ring
Clutch engages abruptly	The car jerks off	Swelling of hydraulic seals	Replace seals
Noise in the clutch mechanism	Increased noise in the clutch mechanism when it is turned on	Destruction of the clutch engagement bearing Increased runout of the thrust ring of the withdrawal levers	Replace bearing Adjust the shutdown mechanism by the exhibition of levers
Clutch Engagement Delay	The car starts with a delay after releasing the pedal	Solidification of fluid in the hydraulic system Jamming of the follower piston Seizures in the connections of the drive disks	Flush the hydraulic system Replace follower piston seal Eliminate bullying

This article describes the process of repair (restoration) of the Kamaz cab. At the beginning of the article, we will consider a step-by-step analysis of the Kamaz cab, and at the end of the article we will watch a video of repairing the Kamaz cab with our own hands, and in particular, all welding work necessary for repairing the cab will be considered. So let's go!

To remove the cabin:

• lift the front facing panel of the cabin;
• disconnect the plug-in block of the electric wiring of the sidelights;
• turn out bolts of fastening of the forward buffer and remove it;
• disconnect the plug-in blocks of the right and left bundles of electrical wiring;
• disconnect the intermediate rod of the brake valve from the bracket located on the left side member by unpinning and removing the rod pin;
• disconnect the fuel control rod;
• disconnect the hydraulic hose of the pneumatic clutch booster and drain the fluid from the hydraulic drive;
• release air from the receivers of the circuits and disconnect all air hoses mounted on the brackets of the cab front panel;
• unpin and unscrew the wedge nut of the propeller shaft of the steering, knock out the wedge with a soft metal drift;
• disconnect the cardan shaft of a steering;
• Disconnect the radiator shutter drive cable;
• close the cock of the cab heater and disconnect the coolant inlet and outlet hose;
• remove the lock washers from the right and left pins of the front brackets of the cabin supports; open the locks on the left and right sides, release the safety hook and tilt the cab 42°;
• unpin and remove the pin of the cab lift limiter located on the cab bracket;
• while supporting the cab, tilt it 60°;
• unscrew the coupling bolts and remove the torsion bar levers;
• open the cabin doors;
• bring the beam crane and, using the device, grab the cab by the upper shelves of the doorways;
• while supporting the cab with a beam crane, unpin and remove the pin of the lower post of the cab limiter;
• carefully lower the cab to its original position;
• unload the axle of the cab front supports by lifting the cab with a beam crane, remove the axles from the right and left brackets;
• lift the cab with a beam crane and place it on a stand.

Remove the front supports only after removing the cab. To remove the lower and upper brackets, unscrew the bolts securing them to the frame and to the transverse beam of the cab floor. The top brackets are fixed in the floor to floating plates with threaded holes, which, if necessary, can be replaced from inside the cab through the oval holes in the floor or through the hole for the steering column by bending the antennae of the floor beam inserts that fix them.

When installing the bottom brackets, make sure that the holes of both brackets are aligned, and finally tighten the bolts of the top brackets after installing them in the bottom brackets and connecting them with axles, but while the cab is still suspended and the front supports are not loaded with its weight.

Removal and installation of doors. To remove the door, unpin the pin connecting the door opening limiter to the bracket on the inner panel of the door, then unscrew the bolts securing the door hinges to the front pillar of the cab.

Carry out the installation of doors with the installed lock and door lock latch. Before tightening the bolts that secure the hinges to the rack, lock the lock into the second fixed position. To avoid friction between the wedge of the lock and the latch, first insert some gasket 1 ... 1.5 mm thick (preferably polythene) into the latch groove, which is removed after tightening the door hinge bolts. In this case, the gap between the door and the door opening is maintained constant throughout the opening (6 ... 10 mm).

Removing the hatch cover of the inner door panel. In order to provide access to the door mechanisms, as well as the dismantling of the lock mechanisms, power windows, windows, you must first remove the hatch cover of the inner door panel.

To do this, remove the inner handles of the door lock and power window, for which press the plastic socket under the handle and remove the pin of the handle. Then turn out screws of fastening of a cover of the hatch of a door and remove a cover.

Remove the door lock through the hatch of the inner door panel in the following order:

remove the manhole cover;
remove the three drive mounting bolts. By turning the drive, disengage it from the rod and remove it through the hatch;
unscrew the screws securing the lock from the end of the door and remove it through the hatch.
Install the lock in reverse order. When assembling the drive and lock, lubricate all friction surfaces and springs with MZ-10 grease.

To remove the lock retainer, unscrew the screws securing it to the rear post of the cab sidewall.

If the outside door handle lock button is faulty, the button can be removed after the outside handle has been removed. To remove the outer handle, unscrew the two screws through the hatch of the inner door panel, securing it from the side of the inner door panel. When installing the button, do not forget to install the button seal.

Remove the power window through the hatch of the inner door panel in the following order:

• remove the manhole cover;
• use the window lifter handle to move the glass to a position in which the sliding glass holder is located against the hatch;
• through the hatch, remove the clamping bar by unscrewing the mounting bolts;
• unscrew the window lifter mounting screws;
• remove the power window through the sunroof.

When assembling the power window, lubricate all rubbing surfaces with Litol-24 grease.

Remove the sliding door glass in the following order:

• remove the door hatch cover;
• remove the window regulator;
• unscrew the screws of the removable glass seal holder (under the door pocket) and disengage the removable holder from the main holder, then disconnect it from the door seal and remove it through the hatch;
• remove the rubber buffer of the lower glass stop through the hatch;
• lower the glass with your hands, tilt and move forward so that it stands opposite the hatch;
• remove the glass through the hatch.

Adjustment and removal of the rotary window. The glass of the swivel window holds in any position, even with a strong headwind, the spring holder of the lower axis. The ease of turning the window and the reliability of its fixation can be adjusted by tightening the holder screw, for which remove the polyethylene plug of the hole under the lower axis of the window and tighten or loosen the holder adjusting screw with a screwdriver.

To remove the vent glass, unscrew the holder screw and the screws securing the upper axis of the vent. Then, moving the window up, remove the lower axle from the holder and the window seal

Removal and installation of windshields and rear windows should be carried out in the same way in the following order:

• remove the wiper arms;
• remove the rubber lock of the window middle pillar seal;
• remove the metal lining from the joint of the seal edging and the seal edging along the entire perimeter;
• by pressing hands on the upper corners of the glass from the cabin, remove the seal from the aperture flange and, bending the edge of the seal, remove the glass and seal;
• clean the seal from the paste.

To install glass:

• lubricate the grooves of the seal with fresh paste;
• bending the edge of the seal, insert the glass into the seal (it is convenient to do this by placing the seal on the table face up);
• place the edging of the seal so that its junction is at the bottom of the window, and put a metal cladding on the junction of the edging;
• insert the rubber lock of the window middle pillar seal;
• insert a strong twine or cord into the groove (designed to connect the seal to the window opening flange) so that the ends are at the bottom of the seal;
• install the glasses together with the seal in the wind window opening, pressing them from the outside to the flange;
• holding one end of the string, pull smoothly, without jerks, behind its other end, thus pulling the seal valve through the window opening flange. To facilitate this operation, you can use a screwdriver;
• clean the glass and window opening from excess paste;
• install the wiper arms.

When using a seal made of an open profile, it is easier to install the glass by first installing the seal in the opening, and then, bending the edges of the seal, first insert one, then the other glass from the outside (it is easier to do this by inserting the glass from the middle to the edges), and then refill center pillar profile. After that, insert the B-pillar itself, the edging of the seal with the cladding and the B-pillar lock.

To improve the sealing of the glass after installation, rubber adhesive can be introduced between the edge of the seal and the glass in the lower half of the window contour.

Install the sunroof cover in the following order:

• put the vent cover on top of the roof opening;
• from the inside or outside, lift the front of the cover and insert the levers into the lugs of the brackets, moreover, with a movable roller into the lugs of the brackets of the hatch cover, and then lower the hatch cover;
• From the outside, lift the back of the sunroof cover forward and use a screwdriver to insert the rear arms.

If a defect occurs - falling out of the roof hatch cover levers - eliminate the deformation of the brackets 8 against which the hatch cover lever rollers rest.

To remove the heater fans, unscrew the screws securing the fan casing, disconnect the motor leads. Then unscrew the screws securing the rubber-metal flange of the electric motor to the fan volute, and remove the electric motor with the fan impeller. Remove the screw securing the fan impeller to the motor shaft and remove the impeller.

When installing, connect the motor leads to the wires so that the left fan impeller rotates clockwise, and the right fan impeller rotates counterclockwise when viewed from the cab. To do this, at the left fan motor, connect the black lead to the green wire from the wire bundle, and the red motor lead to the ground wire. For the electric motor of the right fan, the opposite is true: the red terminal is with the green beam wire, and the black terminal is with the ground wire.

When using non-reversible electric motors ME 226, it is necessary to distinguish between right and left rotation electric motors, and it is necessary to install an ME 226V left rotation electric motor on the left fan, and an ME 226K right rotation electric motor on the right fan. In this case, connect the green wire from the bundle of wires to the plug on the motor cover, parallel to the plane of the cover, and the earth wire to the plug, parallel to the motor rotation axis.

To remove the heater drive, remove the handles of the valve and control levers by unscrewing the screws, their fastenings, unscrew the screws that secure the drive to the shield under the instrument panel, remove the scale and the drive. Turn out screws of clips of covers of a cable, unpin and remove cables of drives. To remove the levers, unscrew the nut securing the axis of the levers. When assembling the drive, tighten the nut on the axis of the drive handles so that the handles can be easily moved, and cotter it. Lubricate rubbing parts before assembly.
When installing air ducts, the hose supplying air to the left deflector on the instrument panel must pass between the wiper rods.

Remove the seats in the following order:

• tilt the cab;
• remove the lower thermal insulation of the floor;
• unscrew the seat fastening nuts under the cabin floor (four nuts each for the driver and middle passenger seats and six nuts for the outer passenger seat);
• lower the cab and remove the seats.

When installing, fasten the seats only with self-locking nuts. Lubricate all friction surfaces of seat hinges, torsion plates, and movement mechanisms with Litol-24 grease during assembly.

To remove the cab upholstery:

• remove the hook for clothes, the hinges of the curtain of the berth, the ceiling of the berth;
• use a screwdriver to remove the fastening clips of the sidewall upholstery;
• remove the upper, rear and lower upholstery of the sidewall;
• remove the upper part of the rear upholstery (after removing the glass seals of the rear windows, first aid kit);
• remove the roof stalk around the ventilation hatch by removing the pins and paper clips;
• remove the cab lighting cover;
• remove the facings of the nests of seat belts of the berth and the guide of the curtains of the berth;
• remove the clips securing the rear of the roof upholstery and remove it;
• remove the fastening clips of the front part of the roof upholstery and, having fed it back, remove it;
• remove, by removing the fastening clips, the upholstery of the lower part of the back (made of artificial leather with artificial felt);
• remove the side front thermal insulation by removing the plastic clips of their fastening, and then both thermal insulations of the front, by removing the rubber clips of their fastening.

To remove the upholstery and thermal insulation of the floor, the seats must be removed.

Install the cab upholstery in the reverse order, i.e. first the thermal insulation of the front panel, then the sidewalls, first fasten the front part of the roof upholstery, then the rear, then the rear upholstery, then the sidewalls.

It is better to install rubber clips with the help of a special mandrel or a rod inserted into the hole of the paper clip and pulling it out when inserted into the hole.
Installing the front part of the roof lining or roof lining (sleeper cab) is as follows: insert the front part of the lining under the front roof reinforcement, push the lining forward until the side grooves of the lining match with the roof reinforcements. Press the upholstery up against the roof. With an awl through the mounting holes in the upholstery, feel for the mounting holes in the roof reinforcements, align these holes and insert the paper clips. Insert paper clips and other upholstery in the same way. Insert the 5x18 pins with washers into the four holes for fastening the ventilation hatch rod in front and behind the hatch and cotter it in the upper part, and the paper clips into the other four.

To remove the instrument panel, open the instrument panel by unscrewing the two screws in its upper part, the switch panel and disconnect all devices and switches from the wires, then unscrew the fuse bracket mounting bolts (in the middle of the instrument panel). After that, bend the brackets that fix the bundle of wires on the bottom of the instrument panel, and remove the bundle together with the fuse bracket from the instrument panel. Remove the hoses from the windshield blower nozzles and the door glass deflectors (it is more convenient to remove these hoses from the air distributor pipes). Remove the bolts securing the lower shields with the cab heater rods, radiator shutters, etc.

Turn out bolts of fastening of the panel of devices to sidewalls, to two lateral kerchiefs, to an arm of a steering column. Unscrew the bolts securing the instrument panel to the front panel (through the openings of the instrument panel, switch panel, glove box, and if the box is not removed, then from below, from under the instrument panel) and remove the instrument panel.

To remove the glove box, open the door, unscrew the screws securing the limiter to the door, the screws securing the box to the bottom wall of the instrument panel and to the racks (from inside the box) or unscrew the racks to the instrument panel (if you need to remove the racks): on the left, opening the switch panel, unscrew two screws, and on the right - from below from under the instrument panel - two bolts. Pull the drawer out and unscrew the door hinges. The spacer between the front and rear of the front fenders may be broken. In this case, cut or break off the remnants of the spacer, drill a through hole in both parts of the wing and, having installed a metal or plastic spacer-spacer with a bolt hole between them, tighten both parts of the wing with a bolt with a self-locking nut.

As promised at the very beginning - a video about do-it-yourself Kamaz cab repair: Welding work.

As always, you can ask your questions on our Kamaz-forum where competent and experienced drivers will answer you.

Total labor intensity - 1350.0 people. min Performer - car repairman of the 5th category

EQUIPMENT, DEVICES, TOOLS
Overhead crane 0=2.0 tf GOST 7890-73; engine disassembly-assembly stand mod. 9194-019, R-770 or R-776; stand for disassembly-assembly of the crankshaft mod. 410-009; flowmeter GOST 11988-72; stand for testing the oil channels of the cylinder block for tightness mod. 470.086; stand for testing the water jacket of the cylinder block for tightness mod. 470.087; hydraulic press R-337; diamond boring machine mod. 2705; pneumatic wrench IP-3113; parts washing machine mod. 196 M or "Typhoon"; gun for blowing parts with compressed air С-417; indicator caliper 18-50 GOST 9244-75; template 8151-4672 to check the distance from the crankshaft to the vverdsha; template for a size of 0.5 mm; set of probes No. 2 GOST 882-75; device for measuring the distance from the connecting rod journal of the crankshaft to the end face of the sealing lug of the cylinder liner mod. 8701-4434; connecting rod bolt elongation control tool 7813-4045; a set of digital branded type 06-7804-4001-01-08; device for checking the runout of the end face of the flywheel relative to the axis of the crankshaft mod. PRI-1P TU 2-034-468-71; dynamometric handle mod. 131 M; torque wrench mod. PIM-1754; suspension for transportation and installation of the engine mod. 130.219.00.000.000; suspension for removal-installation of the hydraulic coupling of the drive assembly with the front cover mod. 170.86; suspension for crankshaft mod. 170.081; hanger for removal-installation of the flywheel mod. 170.012; interchangeable heads 13, 17, 19, 24 mm GOST 25604-83; extension L=250 mm GOST 25600-83; key with connecting square GOST 25601-83; screwdrivers 6.5 mm; 8.0mm; 10.0 mm GOST 17199-71; ring wrench 13 mm GOST 2906-80; steel metalwork hammer GOST 2316-77; copper hammer mod. PIM-1468-17-370; hardwood hammer; metalwork chisel GOST 7211-86; special pliers for removing and installing spring retaining rings I 801.23.000; pliers with elongated jaws GOST 17440-86; insert special for unscrewing and wrapping the eyebolt; lever for turning the crankshaft of the engine 7829-4087 or 7829-4063; connecting rod cap remover I 801.17.000; gear and crankshaft rear counterweight puller AND 801.01.000, crankshaft main bearing cap puller AND 801.18.000; case puller I 801.05.000; PTO half-clutch puller 7700-4188; bearing puller from the rear end of the crankshaft 7700-4186; pin remover 3570; tool for disassembly-assembly of the piston with the connecting rod and rings 7822-4034; piston ring remover and installer I 801. 08.000; tool for pressing cylinder liners into block 7823-4021; mandrel for installing a piston with piston rings in the cylinder liner I 801.00.001-01; mandrel for installing the flywheel housing 7890-4107; device for adjusting the thermal gaps of the engine And 801.14.000; mandrel for removing the housing of the rear bearing of the injection pump drive; brass mandrel for knocking out the piston assembly from the cylinder block; a mandrel with a hook for removing the plugs of the connecting rod journals; mandrel for removing oil deflector with timing gear 7853-4084; mandrel for pressing out the bushing of the upper head of the connecting rod (tubular Dnar = 49 mm, Dvn = 40 mm, L = 100 mm); mandrel for removing and installing the piston pin in the hole of the piston and connecting rod 7853-4045; adapter head (connecting square - screwdriver); mandrel for pressing the bearing into the seat of the rear end of the crankshaft (tubular, Dnar = 52 mm, 28

Dvn=25 mm, L=100 mm); mandrel for pressing the locating pin into the hole of the front end of the crankshaft (Dnar = 25 mm, Din = 14 mm, Lin = 50 mm; Iin = 7 mm); mandrel for pressing crankshaft plugs 7880-4043; mandrel for flaring crankshaft plugs 7860-4042; mandrel for pressing the coupling half * power takeoff (tubular Dnar \u003d 45 mm, Dvn \u003d 28 mm, L \u003d 100 mm;) mandrel for pressing the dowel pin into the hole of the rear end of the crankshaft (Dnar \u003d 25 mm, Dvn \u003d 14 mm, Lout \u003d 50 mm, 1in = 10 mm); Wooden spatula for removing gaskets; locksmith's workbench; heated oil bath mod. 2343; container with dry ice; protective gloves; blacksmith's tongs; hair brush engine oil; napkin GOST 211220-75; container with graphite lubricant; wooden spatula

DISASSEMBLY OF THE KAMAZ-740 ENGINE

Labor intensity -410.0 people. min
1. Install the sub-engine on the stand for disassembly and assembly.

(Crane-beam, suspension, stand).

2. Unscrew the front eyebolt 16 (Fig. 1), remove the adjusting washers 15.

(Special insert).

3. Unscrew the bolts 3 (Fig. 2) with washers 4 fastening the housing 6 of the rear bearing assembly with the cuff 5, remove the housing 6 and the gasket 7 of the housing of the rear bearing of the injection pump drive.

(Replaceable head 17 mm, wrench with p. to., mandrel, hammer, screwdriver 8.0 mm).

4. Remove gear 1 (Fig. 3) of the injection pump drive assembly with shaft 2.

5. Unscrew the bolts 13 (Fig. 4) with washers 25 securing the cylinder head and remove the cylinder head 31 with valves 1 and 21 as an assembly from the cylinder block. (Replaceable head 19 mm, wrench with p. to.).

6. Remove O-ring 34 and cylinder head gasket from cylinder block. (Shovel for removing gaskets).

7. To take out bars of pushers in gathering from the block of cylinders.

8. Repeat work 5-7 for the remaining seven cylinders.

9. Unscrew bolts 5 (Fig. 5) with washers 2 and 3 fastening the hydraulic clutch switch to the discharge pipe and remove the hydraulic clutch switch 1 from the engine. (Wrench ring

10. Unscrew the bolts 3, 49, 50 (Fig. 1) with washers 4, 5, 47, 48 fastening the front cover 6 to the cylinder block 20, remove the fan drive fluid coupling assembly with the front cover 6 and. gasket 44 from the front end of the cylinder block. (Replaceable head 17 mm, wrench with c.c., spatula for removing gaskets, crane-beam, suspension for removing the installation of the hydraulic coupling of the drive assembly with the front cover.

11. Remove the fluid coupling drive shaft.

12. Bend the mustache of the lock washers 40 (Fig. 6), unscrew the bolts 41 fastening with washers of the power take-off coupling half to the crankshaft and remove the power take-off half coupling 39 from the crankshaft 7. (Chisel, hammer, interchangeable head 17 mm, wrench with item k., screwdriver 6.5 mm).

13. Unbend the antennae of the locking plates 12 (Fig. 7) of the bolts securing the flywheel to the crankshaft. Perform work on engines up to No. 75800. (Chisel, hammer).

14. To turn away bolts 11 fastenings of a flywheel. (Replaceable head 19 mm, wrench with p. to.).

15. Remove locking plates 12. Work on engines up to No. 75800.

16. Screw two technological bolts 2 (Fig. 8) into the holes of the flywheel until they stop at the end of the hub and remove the flywheel 1. Screw the bolts alternately by several turns. (Head

Interchangeable 17 mm, crane-beam, hanger for removing and installing the flywheel, wrench with connecting square).

17. Unscrew the bolts 7 and 9 (Fig. 9) fastening with washers 5, 6, 10 and 11 of the flywheel housing to the cylinder block, remove the flywheel housing 2 as an assembly and gasket 1 from the cylinder block. (Heads interchangeable 17 and 19 mm, with p. to., spatula for removing gaskets).

18. Turn the engine on the stand to the upper position with the crankcase of the cylinder block. (Stand).

19. Turn the crankshaft so that the connecting rod journal of the 1st and 5th cylinders is at the bottom dead center (BDC). The numbering of the necks is counted from the front of the crankshaft. (Lever arm).

Rice. 1. Cylinder block with front cover, cylinder liner:

1, 45 - hairpin; 2 - gland of the front cover; 3, 29, 31, 37, 40, 41, 49, 50 - bolt; 4, 30, 48 - spring washer; 5, 38, 46, 47 - flat washer; 6 - block front cover; 7, 8, 11, 32 - cork; 9, 10, 35 - locating pin; 12 - plug of the camshaft hole; 13 - sealing ring; 14 - camshaft bushing; 15 - adjusting washer of the eyebolt; 16 - eye bolt; 17 - bushing with sealing rings, assembled; 18 - bushing sealing ring; 19 - cup cap; 20 - cylinder block; 21 - cylindrical locating pin; 22 - guide pin; 23 - cup cap; 24 - cylinder liner; 25 - upper sealing ring of the sleeve; 26 - sleeve sealing ring; 27 - gasket; 28 - pipe! drain; 33 - plug of the water cavity; 34 - plug gasket; 36 - back cover; main bearing; 39 - main bearing cap; 42 - plug of the water cavity; 43 - cylindrical pin; 44 - block front cover gasket 30

Rice. 4. Cylinder head with valves:
1 - exhaust valve; 2 - exhaust valve seat; 3 - exhaust valve guide sleeve; 4 - valve spring washer; 5 - outer spring of the valve; 6 - internal valve spring; 7 - plate sleeve; 8 - valve cracker; 9 - a bolt of fastening of a cover of a head of the block of cylinders; 10 - flat washer; 11, 25 - washer; 12 - cylinder head cover; 13 - a bolt of fastening of a head of the block of cylinders; 14 - plate of valve springs; 15 - sealing cuff of the intake valve; 16 - cuff ring; 17 - sealing cuff of the inlet valve assembly; 18 - guide sleeve of the intake valve; 19 - inlet valve seat; 20 - inlet valve; 21 - stud for fastening the exhaust manifold pipe; 22 - protective bushing of the pipe gasket; 23 - bracket support; 24 1- stud fastening bracket; 26 - stud for mounting the rack of rocker arms; 27 - cylinder head cover gasket; .28 - pin of the rack of the axis of the rocker arms; 29 - intake manifold mounting screw; 30 - screw fixing the water pipe; 31 - cylinder head; 32 - a plug of a head of the block of cylinders; 33 - plug sealing ring; 34 - sealing ring gas joint

20. Unscrewed!> nuts 11 (Fig. 10) of bolts 9 fastening the cover 10 of the connecting rod of the 1st cylinder to the connecting rod, install the puller shown in Fig. 1 on the connecting rod cover. 11, remove the cover 10 (Fig. 10) of the connecting rod, remove the connecting rod bolts 9 and place them in order on the workbench. Repeat the operation to remove the connecting rod cap of the 5th cylinder. Cylinder numbers must be stamped on the connecting rod caps. (Replaceable head 19 mm, wrench with p. to., locksmith workbench, puller for connecting rod caps).

21. Turn the crankshaft so that the crankpin of the 1st and 5th cylinders is at top dead center (TDC), with light hammer blows through the mandrel on the tides under the bolts of the connecting rod cover of the 5th cylinder, knock out the piston 6 assembly with the connecting rod 8 and rings 2, 3 and 13 from the cylinder block and place on a workbench. Repeat the operation to remove the piston assembly for the 1st cylinder. Cylinder numbers should be stamped on the connecting rods. (A lever for turning the crankshaft, a metal workbench, a brass mandrel for knocking out a piston, a hammer).

22. Remove from the cover 10 of the connecting rod and the lower head of the connecting rod 8 liners 12.

23. Install the cover 10 of the connecting rod on the connecting rod 8, install the fastening bolts 9 and tighten the nuts 11. (Replaceable head 19 mm, wrench with p. to.).

24. Repeat steps 19-23 to remove the remaining 7 connecting rods with piston assembly.

25. Bend the mustache of the lock washer 25 (Fig. 2), unscrew the fastening bolt 1 with washers 25 and 26 of the drive gear 21 of the camshaft drive. (Hammer, chisel, interchangeable head 19 mm, wrench with p. to.).

26. Remove the gear 21 of the camshaft drive assembly with the intermediate gear 2 of the camshaft drive from the axle 16 of the camshaft drive drive gear. (Puller I-801.01.000).

27. Bend the mustache of the lock washers 17, unscrew the bolts 18 of the fastening with the washers of the axle 16 of the camshaft drive drive gear and remove the axle 16 from the cylinder block. (Chisel, hammer, interchangeable head 17 mm, wrench with p. to.).

28. Unscrew the coupling bolts 37 (Fig. 1) of the covers 36, 39 of the crankshaft bearing. (Replaceable head 19 mm, wrench with p. to.).

The water pump is one of the main units that ensure the operation of the cooling system on any car equipped with an internal combustion engine. The speed of circulation of the coolant in the channels of the cylinder block, the removal of excess heat and the maintenance of the optimum operating temperature of the motor depend on the operation of this mechanism. Determining a pump failure is important not only for the cooling system, but for the entire engine. Overheating of the cylinder block, as well as the engine head and valve mechanism, leads to irreversible deformation of the metal, breakdown of the gasket and depressurization of the motor. This entails only one thing - a major overhaul. To avoid such an unpleasant scenario, it is useful to figure out how to quickly and timely replace a motor pump on a KamAZ car.

Cooling system KAMAZ 5511

The engine cooling system is used to maintain a certain temperature of the metal casing of the motor. It is believed that normal heating should not exceed 100 ° C, i.e., the boiling point of water. When calculating and adjusting the thermal clearances of the valves, it is this heating that is taken into account. An increase or decrease in temperature entails an expansion or narrowing of the exhaust gas outlets, affecting the overall power. There is a waste of fuel. That is why, before starting operation, engines always warm up to a temperature of 90–95 ° C.

Location of coolant circulation channels inside the engine

In addition to the water pump, the cooling system includes:

• a radiator located in front of the car (for better airflow);

  The coolant is cooled inside the radiator

• channels inside the engine through which coolant circulates;
• connecting rubber hoses that serve to flow fluid from the engine to the radiator and vice versa;
• an expansion tank that compensates for the change in the volume of antifreeze when heated;

  The expansion tank is used to free-flow the coolant inside the cooling system

• car interior heating system, consisting of a stove radiator and a fan;

  Hot coolant gives off heat to the passenger compartment using a radiator blown by a fan

• thermostats that automatically control the temperature of antifreeze.

  The thermostat is responsible for maintaining the temperature at the same level

The system is closed and fully automatic. Manual control is installed only on the “stove” of the passenger compartment: the driver can independently adjust the level of heating inside the cab.

The system is controlled by an engine temperature sensor located in the motor housing. The sensor readings are displayed on the temperature indicator located on the dashboard.

Thus, all elements that make up the cooling system operate in a static mode.

The only exception is the water pump, which rotates continuously while the engine is running. It is for this reason that the probability of a pump failure is higher than that of other elements of the cooling system.

The location of the water pump on KamAZ

The location of the water pump is determined by the driving mechanism. Rotation is transmitted to the pump pulley from the crankshaft using V-belts. In accordance with this, its location is the left front part of the cylinder block. The design feature is that the forced air fan is located on the fluid coupling, and not on the pump pulley itself.

The water pump is located in front of the engine, on the left - footnote No. 2

Water pump device

The KamAZ car pump consists of the following parts:

Do-it-yourself pump repair

The manufacturers declared the mileage of the new KamAZ car (Euro 3) to be at least 800 thousand km. However, difficult operating conditions, overloads and sudden changes in temperature make their own adjustments. In practice, the pump can withstand 50-60 thousand km. This assumes regular maintenance. The main malfunctions of the water pump 740.63–1307040 are:

• chips and cracks in the pump housing;
• bending or wear of the working shaft;
• wear of the sealing gland;
• bearing wear.

A huge role in the proper operation of the water pump is played by the quality of the coolant (coolant). As you know, antifreeze is designed for 30 thousand kilometers or 2 years of continuous operation. After the expiration of the declared period, the properties of antifreeze change dramatically. This is especially reflected in the lubricating and anti-corrosion properties. The constantly wetted impeller and radiator are covered with rust, the flakes of which clog the ducts and rubbing places. This leads to premature wear of the entire cooling system.

The good news for the motorist is that pumps of this type are available for repair. They are easily and completely disassembled, there are no irreplaceable parts in them.

Chips, cracks and other mechanical damage to the housing (or impeller) are eliminated using electric welding or two-component sealants (such as epoxy). A bent impeller rotation roller can often be leveled with a press or by applying a layer of chromium (with subsequent fine-tuning to standard dimensions). Only the sealing gland, which is quite easy to remove and replace, cannot be repaired.

The adhesive is prepared by mixing the two components in the ratio recommended by the manufacturer.

Diagnosis of malfunctions in the cooling system

Before you start repairing the water pump, you need to make sure that the cause of the engine failure lies precisely in it.

The main indicator by which one can judge the malfunction of the cooling system is the increase in engine temperature during operation. Temperature indicator shows engine temperature above 100°C.

Location of the temperature sensor indicator on the KamAZ dashboard

There may be several reasons:

• low coolant level, coolant leak;
• malfunction of the thermostat;
• malfunction of the radiator;
• failure of the water pump.

The fact of a coolant leak is easy to establish by looking at the expansion tank - it marks the maximum and minimum amount of antifreeze in the system. If the level is below the minimum, then a leak has formed somewhere that needs to be found.

If the thermostat breaks down (and there are two of them in KamAZ 5511), as a rule, the temperature of the liquid drops below the average value. This is due to the fact that a large cooling circle is constantly on. This is also harmful to the engine, but overheating does not occur. If the thermostat is stuck in the “small circle” position, which is extremely rare, the first sign is considered to be a complete shutdown of the heating in the cabin. The coolant boils directly in the expansion tank.

The radiator can either leak or clog. A large amount of dirt and dust adhering to the front of the radiator often leads to overheating of the motor. After washing the cells, the situation, as a rule, normalizes.

If all of the above units are working properly, but the indicator still shows an increased engine temperature, it is worth examining the water pump. Experienced motorists use a few simple but sure tests:

1. A damaged pump begins to make a characteristic sound. The tone changes with increasing rpm, moving from a low "howl" to a high-pitched "squeal".
2. The formation of liquid smudges in the area of ​​\u200b\u200bthe water pump. They are not always obvious, the liquid oozes only at high crankshaft speeds. But an experienced eye will immediately notice specific dirty brown marks on the surface of the cylinder block. The reason is the breakdown of the stuffing box.
3. The third way to determine the malfunction is to manually swing the water pump pulley. To do this, remove the drive belt (belts) and try to swing the pulley up and down. If there is even the slightest play (0.5-1 mm), then there is wear on the shaft or bearing. They need to be changed.

In winter, an indirect sign that may indicate a failure of the pump may be a weak heating of the air in the cabin. Slow coolant circulation leads to the fact that the stove does not cope with its task - it is cold in the cabin.

One of the causes of premature wear of the bearing or the working shaft of the water pump may be excessive tension on the drive belt. It is recommended to check the tension force with a dynamometer or steelyard. After replacing or repairing the unit, it is necessary to correctly adjust the degree of belt tension.

Sometimes it happens that the pump works properly (does not make noise, there is no shaft play and fluid leaks), but the sensor persistently shows the motor overheating. In this case, you need to check the performance of the temperature sensor itself. If a malfunction is found, replace.

What tools are needed to repair a water pump

Starting self-repair, you need to stock up on all the necessary tools and materials. Of the tools you will need:

From the materials you need:

Repair kit for water pump KAMAZ

An excellent help for repairing the pump is a repair kit consisting of original spare parts. It includes all the necessary details:

• working shaft of the pump;
• bearing;
• retaining ring;
• sealing gland assembly;
• gaskets.

Repair kit for water pump KAMAZ

When disassembling a pump, you never know for sure what is damaged in it. The cost of the repair kit is small and is about 5-7 dollars. Having everything you need in stock, the repair is guaranteed to be successful.

Water pump repair Euro2

Before disassembling the water pump, two conditions must be met:

• turn off the engine and let it cool down;
• Drain all coolant completely into a container.

You can not drain the liquid on the ground - it is prohibited by law. Synthetic substances contained in antifreezes and antifreezes poison all living things in their path. Once in the soil, they practically do not decompose and, sooner or later, end up in groundwater, making it unfit for drinking by humans and animals.

The capacity of the KamAZ vehicle cooling system is 18 liters. This means that the container must be sufficiently capacious and clean. If antifreeze has not worked out its resource, it can be reused.

1. The drive belts are removed. The pulley is released.

   Belts are removed by loosening the tensioner

2. Four screws securing the pump to the cylinder block are unscrewed.

   The pump is attached with four screws to the cylinder block

3. The pump is completely removed from the engine.
4. A visual inspection of the unit is carried out, the cause of the breakdown is determined.

For the convenience of dismantling the water pump, a locksmith vice is used.

5. All parts are replaced using the spare parts of the repair kit.
6. Assembly is carried out in the reverse order.

   View of the engine after installing the pump (on the left side)

After installing the pump in the seat of the cylinder block, the fixing screws are tightened. The drive belts are back in place.

The tension of the drive belt is controlled by a special wrench with a dynamometer

When dismantling the pump, it is recommended to cover the seat with a clean rag. This is necessary so that debris or old grease does not get into the cooling system. After installing the pump, it is necessary to thoroughly clean the drive belts and the pulley from oil - it has a destructive effect on the material from which the belts are made. Before installing a new pump, the seat is thoroughly cleaned of oils with a solvent. Otherwise, the sealant on the gasket will not perform its function.

The last steps to complete the repair:

• fill the system with coolant;
• start the engine and warm it up to working condition;
• test the operation of the cooling system at a frequency of up to 2 thousand revolutions per minute;
• turn off the engine and, if necessary, add coolant to the normal level.

Video: pump replacement at KamAZ

The cost of a new original water pump for a KamAZ car ranges from $150 to $200. The price of a repair kit is about $6. Obviously, self-replacement will be much cheaper, even if you have to completely replace the coolant in the system.