Removal, inspection and installation of the camshaft of the ZMZ-402 GAZ-2705 engine
Remove fan drive belt
Remove alternator drive belt
Unscrew four bolts 1, remove fan 2 and fan pulley 3.
Unscrew the four bolts 4 and remove the pulley 5 of the water pump.
Unscrew three nuts 2 and remove fan drive 1.
Unscrew bolt 3 and nut 5, remove bracket 4 with tension roller.
Unscrew 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.
Unscrew the remaining nuts 1 and remove the cover 2 of the camshaft sprockets.
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.
Remove the ignition distributor drive.
Remove oil filter.
Remove fuel pump.
Remove rocker cover.
Remove the valve rocker shaft with racks as an assembly.
Remove the pusher rods, having previously marked them with the valve number.
Loosen nuts 1 and remove the cover 2 of the pushers together with the gasket
Remove pushers 1
Remove bolt 1 and remove camshaft sprocket 2 with a puller.
Remove bolts 3 and remove camshaft thrust flange with spacer sleeve.
Carefully remove camshaft from cylinder block.
Inspection
After removal, wash all parts with gasoline, wipe and dry. Check 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.
Check the push rods.
Replace bent rods. If signs of wear, scuffing, shells are visible 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.
Check pushers. If there are signs of wear, pitting, scuffing, etc. on the working surfaces, replace the pushers.
If the camshaft sprocket is damaged or cracked, it must be replaced.
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 a torque of 55–60 N m (5.5–6.0 kgf m).
Using a feeler gauge, measure the gap between the camshaft thrust flange and the gear wheel hub, it should be within 0.1–0.2 mm.
Installation
Install the camshaft in the reverse order of removal.
Before installing, lubricate the camshaft journals and cams, tappets and tappet rods with engine oil. After installation, adjust the valve clearances.