The engine must be thoroughly cleaned of dirt before disassembly

Disassembly and assembly of the engine is recommended to be carried out on a stand that allows you to install the engine in positions that provide free access to all parts during disassembly and assembly.

Disassembly and assembly of engines must be carried out with a tool of the appropriate size (wrenches, pullers, fixtures), the working surface of which must be in good condition.

With an individual repair method, parts suitable for further work must be installed in their original places.

To do this, such parts as pistons, piston pins, piston rings, connecting rods, liners, valves, hydraulic pushers, etc., when removing them from the engine, must be marked in any way that does not cause damage to parts (punching, inscription, attaching tags and etc.), or stack them on racks with numbered compartments, in the order corresponding to their location on the engine.

With an impersonal method of repairing engines, it must be remembered that connecting rod caps with connecting rods, main bearing caps with a cylinder block, camshaft bearing caps with a cylinder head are processed as an assembly, and therefore they cannot be dismantled.

The crankshaft, flywheel and clutch are factory balanced separately so they are interchangeable. The clutch housing is machined separately from the cylinder block and is also interchangeable. In hydraulic tensioners, disassembly of the body with a plunger is not allowed.

It is recommended to disassemble the engine in the following order:

  • - remove the clutch release fork;
  • - remove the gearbox from the engine;
  • - remove the fan; - remove the clutch housing and starter;
  • - install the engine on the stand for disassembly;
  • - loosen the bolts securing the pulley to the coca coolant;
  • - loosen the tension roller mounting bolt;
  • - loosen the tension of the belt by unscrewing the bolt for moving the tension roller, remove the belt;
  • - unscrew the bolts securing the coolant pump pulley, remove the pulley, pulley reflector;
  • - remove the wires with tips from the spark plugs, unscrew the spark plugs;
  • - disconnect the high voltage wires from the connectors of the ignition coils, remove the wires as an assembly with lugs;
  • - unscrew the union nuts from the fittings of the intake pipe and exhaust manifold, remove the recirculation pipe;
  • - unscrew the valve cover bolts, remove the valve cover assembly with ignition coils, bolts, brackets and washers;
  • - remove the fuel line from the fuel pump to the fuel fine filter;
  • - remove the fuel pump;
  • - remove the front cover of the cylinder head;
  • - remove the upper and middle chain guides;
  • - remove the cover with the gasket of the upper hydraulic chain tensioner;
  • - remove the hydraulic tensioner;
  • - unscrew the bolt securing the intake camshaft sprocket, remove the eccentric and sprocket;
  • - remove the drive chain from the camshaft sprockets;
  • - remove the sprocket from the exhaust camshaft;
  • - unscrew the bolts securing the camshaft covers, remove the covers, thrust flanges;
  • - remove camshafts;
  • - remove the hydraulic pushers using a suction cup or a magnet, arrange them in the order of the numbering of the cylinders;
  • - loosen the screws of the hose clamps for heating the intake tract, remove the hoses from the fittings;
  • - loosen the pinch bolt of the upper bracket of the generator;
  • - unscrew the nut of the bolt securing the generator to the upper bracket, remove the bolt, bushing; - unscrew the bolt nut securing the generator to the bottom bracket, remove the generator;
  • - remove the hoses of the recirculation system from the fittings of the carburetor, thermal vacuum switch, recirculation valve;
  • - loosen the screw of the fuel pipe clamp on the carburetor fitting, remove the hose from the fitting;
  • - unscrew the carburetor mounting nuts, remove the washers, carburetor, gaskets, spacer;
  • - unscrew the nuts securing the recirculation valve, remove the washers, valve, gasket;
  • - unscrew the fastening bolt of the fuel fine filter, remove the filter assembly with fuel pipes;
  • - unscrew the thermal vacuum switch;
  • - unscrew the intake pipe mounting nuts, remove the intake pipe washers, gasket;
  • - unscrew the exhaust manifold fastening nuts, remove washers, exhaust manifold, gaskets;
  • - loosen the thermostat housing hose clamps;
  • - unscrew the screws securing the thermostat housing, remove the housing, gasket;
  • - unscrew the fitting of the oil pressure sensors;
  • - unscrew the bolts of the cylinder head, remove the bolts with washers; - remove the cylinder head;

valve spring removal in

  • - using a tool to dismantle the valve springs. In order for the plate of valve springs to come off the crackers, after compressing the springs, lightly hit the fixture plate with the hammer handle; - remove the valves, arrange them in the order of the numbering of the cylinders;
  • - remove the oil seals from the guide bushings with a puller. It is recommended to remove the valves when repairing the cylinder head;
  • - turn the engine over with the oil sump up; - unscrew the bolts securing the clutch crankcase booster to the block, remove the washers, the booster;
  • - unscrew the bolts and nuts of the oil sump, remove the washers, oil sump, gasket;
  • - unscrew the bolt of the oil pump holder on the third main bearing cap;
  • - unscrew the oil pump mounting bolts, remove the oil pump, gasket, oil pump drive hexagonal shaft;
  • - unscrew the crankshaft coupling bolt, remove the bolt, spring washer;
  • - using a tool, remove the crankshaft pulley;
  • - unscrew the bolts securing the coolant pump to the chain cover, remove the bolts with washers, coolant pump, gasket;
  • - unscrew the tension roller mounting bolt, remove the tension roller;
  • - remove the cover and gasket of the first stage hydraulic tensioner, remove the hydraulic tensioner;
  • - unscrew the synchronization sensor mounting bolt, remove the sensor;
  • - unscrew the screws securing the chain cover, remove the cover, lower generator bracket;
  • - remove the chain of the second stage of the camshaft drive from the intermediate shaft drive sprocket;
  • - unlock the bolts of the intermediate shaft sprockets, remove the sprockets, chain;
  • - unscrew the bolts of the intermediate shaft flange, remove the bolts with washers, flange;
  • - unscrew the bolts of the oil pump drive cover, remove the cover, gasket;
  • - unscrew the nut of the drive gear of the oil pump drive, remove the gear assembly with the nut;
  • - remove intermediate shaft;
  • - press the key out of the intermediate shaft;
  • - use a puller to remove the bushing and sprocket from the crankshaft;
  • - unscrew the bolt securing the shoe of the chain tensioner of the first stage of the camshaft drive, remove the shoe;
  • - unscrew the bolt securing the shoe of the chain tensioner of the second stage of the camshaft drive, remove the shoe;
  • - unscrew the shoe bolt extension, remove the extension;
  • - unscrew the bolts of the lower chain damper, remove the damper;
  • - unscrew the nuts securing the covers of the first and fourth connecting rods, remove the connecting rod covers with liners, remove the liners from the beds of the connecting rod caps;
  • - remove pistons with connecting rods from the first and fourth cylinders;
  • - install the crankshaft so that the second and third connecting rod journals are in the upper position, unscrew the nuts securing the covers of the second and third connecting rods, remove the connecting rod covers with liners, remove the liners from the beds of the connecting rod caps;
  • - remove pistons with connecting rods from the second and third cylinders;
  • - insert a slotted mandrel into the slots of the driven disk;
  • - turn off one by one, in several steps, the bolts of the clutch pressure plate, remove the disc;
  • - remove the clutch disc with splined mandrel;
  • - unlock the flywheel mounting bolts, remove the flywheel from the pin;
  • - unscrew the bolts of the rear cover, remove the rear cover assembly with a rubber cuff;
  • - unscrew the bolts of the main bearing caps, remove the bolts;
  • - remove the main bearing caps with a puller, upper crankshaft thrust bearing half washers;
  • - remove the crankshaft, lower half-washers of the crankshaft thrust bearing;
  • - remove the main bearings from the beds of the cylinder block and from the main bearing caps;
  • - install the main bearing caps in the block according to the numbering;
  • - fix the main bearing caps with bolts;
  • - unscrew the knock sensor mounting nut, remove the washer, sensor;
  • - unscrew the oil filter;
  • - unscrew the drain cock from the cylinder block; - remove the connecting rod bearings from the connecting rods; - install the connecting rod caps on the mounting bolts, tighten the nuts;

Removing piston rings from piston

  • - remove the compression oil scraper rings from the pistons using a puller; - remove the retaining rings; - press the piston pins out of the pistons using a tool and a mandrel

Repair of engine ZMZ 405 GAZ-2705

Repair of parts, units fishing, aggregates and engine systems

Cylinder block, pistons, connecting rods, intermediate shaft

The cylinder block with holes in the cylinder walls, water jacket and crankcase or with cracks in the upper plane and ribs supporting the main bearings must be replaced.

As a result of wear, the cylinders of the block acquire the shape of an irregular cone along the length, and an oval along the circumference.

The wear reaches its greatest value in the upper part of the cylinders in the region of the upper compression ring, when the piston is at TDC; the smallest is in the lower part, with the piston position at BDC.

When repairing cylinders, two repair sizes are provided: 1st and 2nd. Pistons and piston rings are produced with the same repair dimensions.

All cylinders of a block should, as a rule, be machined to the same repair size with mm deviations set for cylinders of nominal size, except when it is necessary to “bring out” shallow scratches on the cylinder mirror (within the limits of increasing the cylinder diameter by 0.10 mm) - in this case, only defective cylinders can be repaired.

If there is a limited number of pistons for repair, it is recommended to calculate the diameter deviations for each cylinder (based on the actual size of the piston skirt diameter designed to work in this cylinder with a clearance of 0.036-0.060 mm) and bore the cylinders to these dimensions.</ p>

Deviations in the shape of the cylinders must be within the tolerance range of the dimensional group for the diameter of the cylinder.

Repair of intermediate shaft support bushings consists in replacing them with repair bushings (increased thickness), followed by boring to a nominal or repair size with a tolerance set for

intermediate shaft

nominal size supports - depending on the degree of wear of the shaft bearing journals. Before repairing the supports, it is necessary to remove the pipe 7

When installing repair bushings, it is necessary to ensure that the holes of the oil channels match. Countershaft bearings should be bored in one setting to ensure alignment.

The journals of the intermediate shaft are ground to the repair size with the tolerance established for the journals of the nominal size, in case of wear exceeding the maximum allowable.

Damage of threaded holes in the form of nicks or thread breakage of less than two threads is restored with a tap to the nominal size.

Threaded holes that have worn or stripped threads of more than two threads are restored by cutting an oversized thread, installing threaded drivers with subsequent threading of a nominal size in them, or installing threaded spiral inserts. The latter method is the most efficient and less time consuming.

Crankshaft

In the presence of cracks of any nature, the crankshaft must be replaced.

To remove wear products in the cavities of the connecting rod journals and in the oil channels of the crankshaft, it is necessary to unscrew the neck plugs, flash (with a solution of caustic soda heated to 80 ° C) and clean the cavities and channels with a metal brush.

After cleaning, they must be washed with kerosene, blown and dried with compressed air, then screw the plugs with a torque of 38-42 Nm (3.8-4.2 kgf m).

If the thread in the holes is damaged up to two threads, it is restored with a tap to the nominal size. If two or more threads are torn off, then the repair is carried out as follows:

  • - threads in the holes for the flywheel mounting bolts - by installing threaded spiral inserts;
  • - threads in the hole for the ratchet - by cutting a repair thread; - threads in the holes for plugs - by cutting a repair thread.

Connecting rod and main journals, worn within the repair size, are ground to the nearest repair size (1st, 2nd or 3rd) with the tolerance established for the nominal size journals (all necks are ground to the same repair size).

The sharp edges of the chamfers of the oil channels are blunted with a conical abrasive tool, and then the necks are polished.

Cylinder head, valve train and camshafts

If there are holes, burnouts and cracks on the walls of the combustion chambers and the destruction of the bridges between the valve seats, the cylinder head must be replaced with a new one. The repair of threaded holes is similar to that indicated for the threaded holes of the cylinder block.

Valve spring removal

To check the tightness of the valves, it is necessary to pour kerosene alternately into the inlet and outlet channels of the cylinder head.

The leakage of kerosene from under the valve plates indicates their leakage.

Leaking valves are removed from the cylinder head using a valve spring compressor.

When disassembling, lay the valves in order, corresponding to their location in the head, for their subsequent installation in their original places.

Before lapping the valve, check for warping of the valve disc and burning of the valve and seat. In the presence of these defects, it is impossible to restore the tightness of the valve by lapping, and the seat must first be bored, and the damaged valve replaced with a new one. If the gap between the valve stem and the guide sleeve exceeds 0.20 mm, the valve and sleeve should be replaced with new ones.

For spare parts, valves are produced in nominal size, and guide bushings are produced with an allowance for processing along the inner diameter after being pressed into the head and with an outer diameter of three repair sizes: the first is with an increase of 0.02 mm from the nominal, the second is with an increase by 0.2 mm from the nominal, the third - with an increase of 0.02 mm from the second repair size.

Pressing out the valve guides

The worn guide bushing is pressed out using a mandrel Before the guide bushings are pressed out, it is necessary to determine the maintainability of the cylinder head.

The cylinder head is repairable if, after machining the valve seat, the distance from the camshaft axis to the end of the valve stem pressed against the working chamfer of the seat is at least 35.5 mm.

If this condition is not met, the cylinder head cannot be repaired. The cylinder head is also beyond repair if the surface adjacent to the block has a non-flatness of more than 0.1 mm.

When installing new guide bushings, they must be cooled in carbon dioxide ("dry ice") to a temperature of minus 40-45 ° C, and the cylinder head must be heated to a temperature of plus 160-175 ° C.

The bushings during assembly should be inserted into the head hole freely or with light force.

The bushings of the first repair size are installed in the head without additional processing of the holes in the head, the bushings of the second and third repair sizes are installed with preliminary boring (reaming) of holes up to a diameter of 14.2 mm.

Valve seat profiles

After installing and reaming the bushings, machine the chamfers of the seats (by grinding or boring), centering the tool on the hole in the bushing.

When processing, it is necessary to maintain the dimensions indicated in Fig. 7 and ensure the concentricity of the chamfer on the valve seat with the hole in the sleeve (the runout of the working chamfer of the seat relative to the hole in the sleeve is allowed no more than 0.05 mm).

After chamfering, it is necessary to reduce their width by machining the inner surface of the seats at an angle of 30 ° to the size "c" equal to (2 ± 0.4) mm for the intake valve seats, (2 ± 0.3) mm for the seats exhaust valves.

Then grind the valves using a lapping paste composed of one part M-20 micropowder and two parts I-20A oil.

Before reassembling the cylinder head, it is necessary to clean the combustion chambers and the intake and exhaust channels from soot and deposits, after wetting the soot with kerosene, this prevents the soot from spraying when it is removed and prevents the ingress of toxic dust when breathing.

Wipe and blow them with compressed air. On the installed valve guides, it is necessary to simultaneously install the spring support washers with the help of a mandrel and press on the valve stem seals.

Lubricate the valve stems with the oil used for the engine, insert the valves into the bushings according to the order of their installation and assemble them with the springs using a tool.

Make sure that the crackers have entered the annular grooves of the valves. Pour kerosene into the inlet, outlet channels and make sure the valves are tight. To determine the clearance in the camshaft bearings, you need to install all the bearing caps in accordance with their numbers.

Before installing the covers "1", "2", "3", "4", "5", "6", "7" and "8" of the cylinder head beds, they must be lubricated with engine oil.

Centering of these covers is carried out using a cylindrical mandrel with a diameter of 35–0.02 mm, laid in bed.

After tightening the covers to a torque of 19-23 Nm (1.9-2.3 kgf m), remove the mandrel towards the rear end of the cylinder head (while the rear cover of the cylinder head must be removed).

If the gap in one of the bearings is more than 0.15 mm, then either the cylinder head or the camshaft must be replaced.

The gap in the hole for the hydraulic pusher and the hydraulic pusher should not exceed 0.15 mm. With a larger gap, either the hydraulic pusher or the cylinder head must be replaced.

The surfaces of the bearing journals and cams must be free of scuffs and deep pits and not have wear that exceeds the maximum allowable.

After checking the shafts, it is necessary to clean and polish the surfaces of the necks and cams.

Hydratensioner When repairing an engine, hydraulic tensioners must be disassembled, their parts washed and assembled (“charged”). The hydraulic tensioner is disassembled in the following order:

hydraulic tensioner

  • - unscrew the valve body 1 from the body 4 of the hydraulic tensioner; - remove spring 5 and plunger 3 from housing 4. The hydraulic tensioner is assembled in the following order:

Hydro tensioner assembly mandrel

  • - install the body 4 of the hydraulic tensioner on a vertically fixed mandrel - insert plunger 3 into the body of the hydraulic tensioner until the retaining ring 6 stops on the plunger into the mandrel, having previously lubricated the pair with oil used for the engine;
  • — insert spring 5 into the plunger. Install the valve body 1 of the hydraulic tensioner on the spring and, compressing the spring, wrap it into the body, while the retaining ring on the plunger should be in the groove of the body and prevent the plunger from moving in the body.

Warnings 1. On the assembled hydraulic tensioner, pressing the plunger nose protruding from the body is not allowed in order to prevent the plunger from disengaging from the body under the action of a compressed spring. 2.

It is not allowed to clamp the body of the hydraulic tensioner during assembly in order to avoid violation of the geometry of the plunger pair.

Coolant pump

Disassembly and assembly of the pump are similar to the indicated operations for engines ZMZ-4025, -4026.

To press on the coolant pump hub

The only difference is that when pressing on the bearing roller of the pump pulley hub, the size of (106 ± 0.2) mm should be maintained.

Oil PumpIf there is a malfunction in the lubrication system caused by a malfunction of the oil pump, it needs to be disassembled. For disassembly, you must do the following: - bend the mustache of the mesh frame, remove the frame and mesh;

Oil pump

  • - unscrew four bolts, remove the inlet pipe 7 and partition 6; - remove the driven gear 5 and the roller 3 with the drive gear 7 from the housing;

Reducing valve

  • —remove washer 3, spring 2 and plunger 7 of the pressure reducing valve from the receiving valve

Preparatory operations before assembling engines ZMZ-4061, ZMZ-4063 are the same as before assembling engines ZMZ-4025, ZMZ-4026.

The engine must be assembled in the following order:

  • - fix the cylinder block on the stand, carefully inspect the cylinder mirror, if necessary, remove the unworn belt above the upper compression ring with a scraper.

Metal should be removed flush with the worn surface of the cylinder;

  • - unscrew the plugs of the oil channels and blow out all the oil channels with compressed air, screw the plugs back in place;

Note The crankshaft, flywheel and clutch assembly are not balanced

  • - wipe the beds under the liners in the block and in the main bearing cap with a napkin; - install the upper (with grooves) main bearing shells in the bed of the block, and the lower ones (without grooves) in the bed of the covers;
  • - wipe the liners with a napkin and grease them with engine oil;
  • - wipe the main and connecting rod journals of the crankshaft with a napkin, lubricate them with clean engine oil and install the shaft in the cylinder block;
  • - lubricate with engine oil and install the thrust bearing half washers: the upper ones - in the grooves of the third main bed of the cylinder block (with an anti-friction layer to the crankshaft web); lower - together with the cover of the third main bearing. The antennae of the half washers must go into the grooves of the cover;
  • - install the covers of the remaining supports on the corresponding main journals, wrap and tighten the bolts of the main bearing caps with a torque of 100-110 Nm (10-11 kgf m), after lubricating the threads of the bolts with engine oil;
  • - turn the crankshaft, its rotation should be free with little effort;
  • - take a cover with a rubber seal at the rear end of the crankshaft, check the suitability of the seal for further work. If the oil seal has worn lips or is loose on the crankshaft flange, replace it with a new one.

It is recommended to press the stuffing box into the cover using a mandrel;

  • - fill 2/3 of the cavity between the working edge and the boot of the stuffing box with CIATIM-221 grease, install and fasten the cover to the block with bolts 12-18 Nm (1.2-1.8 kgf m). Center the lid using a mandrel;
  • - install the flywheel on the rear end of the crankshaft so that the hole in the flywheel is aligned with the pin;
  • - install the washer of the flywheel bolts, screw on and tighten the bolts to a torque of 72-80 Nm (7.2-8.0 kgf m);
  • - install a spacer sleeve in the flywheel and press in the ball bearing 80203AC9 with protective washers.

Sub-assembly of the connecting rod and piston group. Selection of pistons to block cylinders, as well as piston pins to pistons and connecting rods, should be carried out at a temperature of parts (20 ± 3) ° C.

Pistons by outer diameter and cylinders by inner diameter are sorted into five size groups.

Pistons of the same size groups as the cylinders must be installed in bored or new block cylinders.

Repair of engine ZMZ 405 GAZ-2705

Selection from neighboring groups is allowed, while, as with the selection of pistons in working cylinders, the selection is made according to the pulling force of the probe tape with a thickness of 0.05 mm and a width of 10 mm.

The probe tape is laid between the cylinder and the piston along the entire height of the piston and is placed in a plane perpendicular to the axis of the piston pin along the largest diameter of the piston. The force on the dynamometer connected to the probe tape should be 35-45 N (3.5-4.5 kgf).

Piston marking - the letter indicating the group is stamped on the piston bottom;

- repair increase is indicated by the inscription "406" (standard size) or "406AP" (repair increase 0.5), or "406BR" (repair increase 1.0), cast on the side wall of one of the bosses for the piston pin.

The letter designating the cylinder group is inked on the outer surface of the block, to the right, opposite each cylinder. For ease of selection, fingers, connecting rods and pistons are divided into four size groups as they decrease in size.

Repair of engine ZMZ 405 GAZ-2705

Marking of pins and connecting rods Pins and connecting rods are marked with paint: the pin is on the inner surface, the connecting rod is on the head rod. Piston - Roman numerals (knockout) on the bottom or paint on the weight boss.

The piston pin is matched to a connecting rod belonging to the same or neighboring group with a clearance of 0.0045 to 0.0095 mm.

When selecting, the piston pin should fit snugly, but without jamming, into the hole in the upper head of the connecting rod under the force of the thumb. The piston pin should be lightly lubricated with engine oil.

Since the linear expansion of the piston material is approximately 2 times greater than that of the pin material, at normal room temperature the pin enters the bore of the piston bosses with an interference fit.

The size groups of the piston and pin must match. The piston complete with piston pin, piston rings and connecting rod assembly must be controlled by weight. The difference in weight sets for one engine should not exceed 10 g.

After assembling the pistons and piston pins, it is necessary to continue the subassembly of the connecting rod and piston group in the following order:

  • - clean the bottoms of the pistons and the grooves for the piston rings from carbon deposits;
  • - press the piston pin into the piston and connecting rod using a tool. In this case, heat the piston to a temperature of 60-80 ° C (pressing a finger into a cold piston can damage the surface of the holes in the piston bosses, as well as deformation of the piston itself).

The connecting rods and pistons must be oriented as follows before assembly with the piston pin:

  • - the arrow on the bottom of the piston (or the inscription "FRONT" located on the outer side of the boss under the finger), the ledge on the side surface of the connecting rod cap and the ledge on the crank head of the connecting rod must be directed in one direction;

Repair of engine ZMZ 405 GAZ-2705

  • - select piston rings according to the cylinders. The thermal gap measured in the locks of the rings placed in the cylinder should be 0.3-0.6 mm for the compression rings and 0.5-1.0 mm for the steel disks of the oil scraper rings.

In worn cylinders, make the smallest gap 0.3 mm for compression rings and 0.5 mm for steel disks of oil scraper rings;

Repair of engine ZMZ 405 GAZ-2705

  • - check the gap between the rings and the wall of the piston groove with a feeler gauge. Check the circumference of the piston at several points.

The gap size should be for the top its and the lower compression rings within 0.050-0.087 mm, for the prefabricated oil scraper ring - 0.115-0.365 mm;

Repair of engine ZMZ 405 GAZ-2705

  • - put the piston rings on the piston using the tool. Place the lower compression ring with the inner recess up to the piston crown. The rings in the grooves must move freely;
  • - insert pistons into cylinders like this:
  • - orient the connecting rod and piston group in such a way that the arrow on the piston bottom (or the inscription "FRONT" on the boss) faces forward;
  • - wipe the beds of the connecting rods and their caps with a napkin, wipe and insert the liners into them;
  • - turn the crankshaft so that the cranks of the first and fourth cylinders take the position corresponding to BDC;
  • - lubricate the liners, piston, connecting rod journal and the first cylinder with clean engine oil;
  • - move the locks of the compression rings at an angle of 180° to each other, the locks of the oil scraper discs also at an angle of 180° to each other and 90° in relation to the locks of the compression rings.

In this case, set the lock of the two-function expander at an angle of 45° to the lock of one of the annular discs;

  • - put protective brass tips on the connecting rod bolts, compress the rings by crimping or using a mandrel for installation in the piston cylinder;

Repair of engine ZMZ 405 GAZ-2705

  • - insert the piston into the cylinder. Before installing the piston, you should once again make sure that the numbers stamped on the connecting rod and its cover correspond to the serial number of the cylinder, check the correct position of the piston and connecting rod in the cylinder;
  • - pull the connecting rod by the crank head to the connecting rod neck, remove the brass tips from the bolts, put on the connecting rod cover. The connecting rod cover should be installed so that the numbers stamped on the cover and connecting rod face the same direction. Tighten the nuts with a torque wrench to a torque of 68-75 Nm (6.8-7.5 kgf m);
  • - insert the piston of the fourth cylinder in the same order;
  • - turn the crankshaft 180° and insert the pistons of the second and third cylinders;
  • - rotate the crankshaft several times, which should rotate easily with little effort;
  • - install the oil pump holder and the oil pump on the block and fix them;
  • - lubricate the intermediate shaft bushings with engine oil, install the key in the groove on the intermediate shaft shank and install the shaft in the cylinder block until the shank exits;
  • - install the oil pump drive gear with nut on the intermediate shaft shank and tighten the gear nut;
  • - install and secure the intermediate shaft flange, while the smaller diameter of the hole on the flange should be adjacent to the block;
  • - lubricate the roller with the driven gear of the oil pump drive with engine oil and insert it into the hole in the block until the gears of the oil pump drive engage;
  • - insert the hexagonal shaft of the oil pump drive into the hole of the roller sleeve;
  • - install the gasket and the cover of the oil pump drive, fix the cover;
  • - install camshaft drives in the following order:

crankshaft front end

  • - press sprocket 6 onto the crankshaft shank;
  • - install rubber sealing ring 12 and bushing 5 with a large internal chamfer to the sealing ring on the crankshaft shank;
  • - install the crankshaft pulley key into the keyway;

Camshaft drive

  • - turn the engine crankshaft until the mark on the crankshaft sprocket matches the mark "M2" on the cylinder block, which will correspond to the position of the piston of the first cylinder at TDC. In this case, the mark on the cylinder block must be located symmetrically relative to the axis of the cavity of the sprocket teeth;
  • - install the lower chain damper 19 without completely tightening the fastening bolts;
  • - put the chain 6 on the driven sprocket 7 (number of teeth - 38) of the intermediate shaft and on the sprocket 1 of the engine crankshaft. Install the sprocket with the chain on the intermediate shaft, while the mark on the driven sprocket of the intermediate shaft must match the mark "M1" on the cylinder block, and the leading branch of the chain passing through the damper must be tensioned;
  • - install the drive sprocket 8 (the number of teeth - 19) of the intermediate shaft and fix the sprockets on the intermediate shaft with bolts. Bend the locking plate on the edge of the bolts;
  • - install shoe 5 of the hydraulic tensioner of the chain of the first stage (lower chain) of the camshaft drive;
  • - pressing the hydraulic tensioner shoe, tension the chain, check the correct installation of the sprockets according to the marks and finally fix the lower damper 19.
  • After installing the intermediate shaft drive chain, the rotation of the crankshaft is not allowed until the camshaft drive chain and hydraulic tensioners are installed;
  • - install shoe 9 of the hydraulic chain tensioner of the second stage (upper chain) of the camshaft drive;
  • - put on the drive sprocket 8 of the intermediate shaft the chain 11 of the second stage of the camshaft drive;
  • - take a chain cover with a rubber gland, check the suitability of the gland for further work. If the oil seal has worn lips or is loose on the crankshaft bushing, replace it with a new one. It is recommended to press the stuffing box into the cover using a mandrel;
  • - fill 2/3 of the cavity between the working edge and the anther of the stuffing box with CIATIM -221 grease;
  • - while holding the second stage chain from jumping off the intermediate shaft sprocket, install and secure the chain cover and at the same time the generator bracket, tighten the screws to a torque of 22-27 Nm (2.2-2.7 kgf m);
  • - install and fix the coolant pump on the chain cover by tightening the bolt that secures the pump to the chain cover to a torque of 22-27 Nm (2.2-2.7 kgf m);
  • - lubricate the hole for the hydraulic tensioner in the chain cover with engine oil and install the assembled hydraulic tensioner 2 until it touches the shoe stop, but do not press, in order to prevent the hydraulic tensioner lock from actuating; - install a noise-insulating rubber washer 3 in the cover of the hydraulic tensioner;
  • - close the hydraulic tensioner with a cover and fix it with two bolts;
  • - press the mandrel through the hole in the hydraulic tensioner cover onto the hydraulic tensioner, moving it until it stops, then release it, while the locking ring on the plunger will disengage from the hydraulic tensioner body and allow the plunger and body to move under the action of the spring. The body will move all the way to the washer in the cover, and the chain will be tensioned through the shoe;
  • - screw plug 4 into the hydraulic tensioner cover;
  • - install a hose connecting the pump nozzle with the thermostat housing nozzle on the coolant pump nozzle;
  • - apply a thin layer of adhesive-sealant Elastosil 137-83 on the horizontal end of the chain cover and the joint of the chain cover with the cylinder block;
  • - install the cylinder head gasket on the block guide bushings and also apply Elastosil 137-83 adhesive sealant to the surface of the gasket located above the chain cover;
  • - install the assembled cylinder head on the block and tighten the head bolts in two stages - pre-tightening with a torque of 40-60 Nm (4-6 kgf m) and final - 130-145 Nm (13.0-14, 5 kgf m).

Head tightening diagram

The cylinder head bolt tightening sequence is shown in the figure. Lubricate the threads of the bolts with oil before installation;

  • - unscrew the bolts and remove the camshaft covers, wipe the beds under the camshafts in the head and in the covers with a napkin;
  • - lubricate the holes in the head for the hydraulic pushers with engine oil used for the engine and install the hydraulic pushers in the cylinder head.

When repairing the engine without replacing the hydraulic pushers, install them in accordance with the markings applied to them during disassembly; if the hydraulic pusher fails, it must be replaced, since it cannot be repaired. It is necessary to remove the hydraulic pushers with a suction cup or a magnet;

  • - install the camshafts on the cylinder head, having previously lubricated the beds in the head, the cams and the bearing journals of the camshafts with engine oil.

The intake camshaft is installed with the sprocket pin up and the exhaust camshaft with the sprocket pin to the right. Due to the angular arrangement of the cams, these positions of the camshafts are stable;

  • - install the front cover of the camshafts with the thrust flanges installed in it on the mounting sleeves, while due to the longitudinal movement of the camshafts, ensure the installation of the thrust flanges into the grooves;
  • - install covers No. 3 and No. 7 of the camshafts and pre-tighten the bolts of the covers until the surface of the covers touches the upper plane of the cylinder head;
  • - install all other covers in accordance with the marking and pre-tighten the bolts of the covers;
  • - finally tighten the bolts for fastening the camshaft covers to a torque of 19-23 Nm (1.9-2.3 kgf m);
  • - lubricate all cam camshafts with engine oil and check the rotation of each camshaft in the supports, for which turn the camshaft with a wrench using a special square on the camshaft until the valve springs of one of the cylinders are fully compressed.

With further cranking, the camshaft should rotate independently under the action of the valve springs until the next cams touch the tappets;

set stars, labels

  • - check the ease of rotation of the camshafts and then turn them so that the locating pins 13 (see Fig. 22) under the sprockets are approximately horizontal and directed in different directions.

The given positions of the camshafts are stable and provided by the angular arrangement of the cams;

  • - start checking the installation of the angular position of the camshafts from the exhaust valve shaft.

To do this, throwing a drive chain on the sprocket 16, install the sprocket on the flange and the camshaft pin, while turning the camshaft clockwise by the square to match the pin and the hole on the sprocket.

By turning the camshaft counterclockwise, tighten the drive branch of the chain, while the mark 12 on the sprocket should coincide with the upper plane of the cylinder head 17. The crankshaft must not be allowed to turn;

  • - for angular installation of the exhaust camshaft, put the drive chain on the sprocket 14, install the sprocket on the flange and the camshaft pin with a slightly sagging branch of the chain between the sprockets.

By turning the camshaft counterclockwise, tighten the chain, while mark 12 on the sprocket should coincide with the upper plane of the cylinder head;

  • - insert the fuel pump drive eccentric into the socket of the intake camshaft sprocket;
  • - install and tighten to a torque of 46-74 Nm (4.6-7.4 kgf m) the bolts for fastening the sprockets (and the eccentric on the intake camshaft), holding the camshafts from turning with a key for the square;
  • - install the hydraulic tensioner 10 of the upper chain of the camshaft drive in the same way as installing the hydraulic tensioner of the chain of the lower chain;
  • - install the middle 18 and the top 15 chain guides without completely tightening the fastening bolts;
  • - tighten the working branches of the second stage chain by turning the engine crankshaft in the direction of rotation and finally fix the middle and upper chain guides;
  • - install the pulley on the crankshaft shank until it stops and screw in the bolt with a torque of 104-128 Nm (10.4-12.8 kgf m);
  • - to control the installation of camshafts at the end of the assembly. To do this, rotate the engine crankshaft two turns in the direction of rotation until the mark on the crankshaft damper matches the mark on the chain cover. In this case, the marks on the camshaft sprockets must coincide with the upper plane of the cylinder head;
  • - when repairing the engine associated with the removal of camshafts, cylinder heads and sprockets on the intermediate shaft, install the camshaft drive during assembly as described above;
  • - if the intermediate shaft sprockets and the chain cover are not removed during the repair, then before disassembling it is necessary to set the piston of the 1st cylinder to the TDC position on the compression stroke, while the line on the crankshaft pulley must coincide with the protrusion on the chain cover , and the marks on the camshaft sprockets must be horizontal, directed in different directions and coincide with the upper plane of the cylinders.

After removing the camshafts and cylinder head, the crankshaft can only be rotated back to its original position or 2 turns.

Turning the crankshaft 1 turn, even if the marks on the pulley and the chain cover match, will lead to incorrect timing.

If the camshafts and sprockets are installed incorrectly, the marks on the sprockets will not match the upper plane of the cylinder head. In this case, it is necessary to remove the sprockets, turn the crankshaft in the direction of rotation by 1 turn and repeat the installation of the sprockets, as described above;

  • - install and secure the coolant pump pulley;
  • - assemble the front cylinder head cover with the fuel pump intermediate lever and spring;
  • - install and secure the front cover of the cylinder head;
  • - install the thermostat housing pipe in the hose on the coolant pump pipe and fix the thermostat housing on the cylinder head, tighten the hose clamps;
  • - install exhaust manifold, engine lift bracket and the bracket of the water intake pipe on the exhaust manifold studs, screw on and tighten the fastening nuts;
  • - press the tube of the rod oil level indicator and install the indicator;
  • - install and secure the valve cover;
  • - install and secure the top bracket of the generator and at the same time the bracket for lifting the front engine;
  • - install and fix the tension roller;
  • - install and secure the inlet pipe;
  • - lubricate the joints of the lower flange of the cylinder block with the chain cover and with the rear cover with Elastosil 137-83 adhesive-sealant or UN-25 paste;
  • - install the oil pan gasket on the lower flange of the cylinder block;
  • - install and secure the oil pan and clutch booster;
  • - install and secure the clutch driven and pressure plates, centering the driven disc with a mandrel;
  • - put engine parts and assemblies in reverse order;
  • - remove the engine from the stand, install and attach the clutch housing to the cylinder block;
  • - lubricate and put on the front cover of the gearbox the clutch release assembly with bearing;
  • - put and fix the gearbox;
  • - put the clutch release fork.