Removing and installing the camshaft of the ZMZ-402 engine

  • 1. Remove the fan drive belt.
  • 2. Remove the alternator drive belt.

Removing and installing 402 engine camshaft

  • 3. Remove four screws 1, remove fan 2 and fan pulley 3.

Unscrew the four bolts 4 and remove the water pump pulley 5.

Removing and installing 402 engine camshaft

  • 4. Unscrew three nuts 2 and remove fan drive 1.

Unscrew bolt 3 and nut 5, remove bracket 4 with tension roller.

Remove six bolts 7 and remove crankshaft pulley 6 with vibration damper assembly.

Unscrew the coupling bolt 8 (or ratchet) with a puller, remove the crankshaft pulley hub.

Removing and installing 402 engine camshaftRemoving and installing engine camshaft 402

  • 5. Loosen the remaining nuts 1 and remove the cover 2 of the camshaft sprockets.
  • 6. Install the piston of the 1st cylinder in the TDC. compression stroke.

To do this, turn the crankshaft so that the marks on the crankshaft sprocket and the camshaft gear are aligned.

Removing and installing 402 engine camshaft

  • 7. Remove the ignition distributor drive.
  • 8. Remove the oil filter.
  • 9. Remove fuel pump.
  • 10. Remove rocker cover.
  • 11. Remove the valve rocker shaft with strut assemblies.
  • 12. Remove the pusher rods, having previously marked them with the valve number.
  • 13. Loosen nuts 1 and remove pusher cover 2 together with gasket.

Removing and installing 402 engine camshaftRemoving and installing engine camshaft 402

  • 14. Pull out pushrods 1.
  • 15. Remove bolt 1 and remove camshaft sprocket 2 with a puller.

Remove bolts 3 and remove the camshaft thrust flange with spacer

  • 16. Carefully remove the camshaft from the cylinder block.


  • 1. After removing, wash all parts with gasoline, wipe and dry.

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

Measure the diameters of the camshaft journals,

  • 2. Check the push rods. Replace bent rods. If there are signs of wear, scuffing, shells on the tips of the rods, the rods should also be replaced.

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

  • 3. Check pushers. If there are signs of wear, pitting, scuffing, etc. on the working surfaces, replace the pushers.
  • 4. If the camshaft gear is damaged or cracked, it must be replaced.
  • 5. Measure the axial clearance of the camshaft. To do this, assemble the 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 tighten the gear wheel mounting bolt with a washer.

Tighten the bolt to 55–60 Nm (5.5–6.0 kgf m).

Measure the gap between the thrust flange of the camshaft and the hub of the gear wheel with a feeler gauge, it should be within 0.1–0.2 mm.


Install the camshaft in the reverse order of removal.

Before installing, lubricate the camshaft journals and cams, tappets and pushrods with engine oil.

After installation, adjust check valve clearances.