The removal of the camshaft was discussed in the article - "How to disassemble the ZMZ-402 engine"

Some motorists pay little attention to the condition of the camshaft when repairing the engine.

The main focus is on the CPU and crankshaft.

Which adversely affects the further operation of the engine.

Special attention should be paid to the camshaft and its bearings.

In case of severe wear of the camshaft bushings, new bushings must be pressed.

Install a new camshaft.

Inspection and defect of the camshaft

Осмотр и дефектация распределительного вала ЗМЗ-402

After removal, rinse all parts with gasoline, wipe and dry.

Inspect the camshaft.

If there are bullies, deep scratches, shells, chips, cracks on the necks, cams and gear of the oil pump drive, replace the camshaft.

Осмотр и дефектация распределительного вала ЗМЗ-402

Inspect the push rods. Bent rods should be replaced.

If there are signs of wear on the tips of the rods, the bullies, shells, rods should also be replaced.

It should be noted that the length of the rod of the mod. 402 engine is 283 mm, and the length of the mod. 4021 engine is 287 mm.

Measure the diameters of the camshaft necks, the nominal diameters of the necks are indicated in the table.

Inspect the pushers.

If signs of wear, sinks, bullies, etc. are visible on the work surfaces, replace the pushers.

Осмотр и дефектация распределительного вала ЗМЗ-402

If the teeth on the camshaft gear are damaged or there are cracks, it needs to be replaced.

Measure the axial clearance of the camshaft.

To do this, pick up a shaft with a gear wheel, put a spacer ring and a thrust flange on the front end of the camshaft, then press the gear wheel and wrap the gear mounting bolt with a washer.

Tighten the bolt with a torque of 55-60 Nm (5.5-6.0 kgf * m).

With a probe, measure the gap between the thrust flange of the camshaft and the hub of the gear wheel, it should be within 0.1-0.2 mm.

Втулки-подшипники распределительного вала ЗМЗ-402

Install the camshaft in the reverse order of removal.

Before installation, lubricate the camshaft necks and cams, pushers and push rods with engine oil. After installation, adjust the gaps in the valve actuator.

Nominal dimensions and fit of mating parts of the camshaft of the engine mod. 402

Part Name

Nominal

diameter, mm

Name mated details

Nominal

diameter, mm

The first neck

camshaft

52,0 -0,02

Cylinder block

52,0 +0,075

52,0 +0,05

The second neck

camshaft

51,0 -0,02

Cylinder block

51,0 +0,075

51,0 +0,05

The third neck

camshaft

50,0 -0,02

Cylinder block

50,0 +0,05

The fourth neck

camshaft

49,0 -0,02

Cylinder block

49,0 +0,075

49,0 +0,05

Fifth neck

camshaft

48,0 -0,02

Cylinder block

48,0 +0,075

48,0 +0,05

Gear wheel

28,0 +0,023

Distribution shaft

28,0 +0,023

28,0 +0,002

Valve tappet

25,0 -0,008

25,0 -0,022

Cylinder block

25,0 +0,023

Tip of the pusher rod

8,75 +0,03

8,75 -0,02

Pusher rod

8,75 +0,045

8,75 -0,035

Part Name

Gap, mm

Tension, mm

min

max

min

max

The first camshaft neck

0,05

0,095

Second camshaft neck

0,05

0,095

Third camshaft neck

0,05

0,095

Fourth camshaft neck

0,05

0,095

Fifth camshaft neck

0,05

0,095

Gear wheel

0,021

0,023

Valve tappet

0,015

0,038

Tip of the pusher rod

0,005

0,065