Adjusting the valve clearances of the engine 402 GAZ-3110
The adjustment of the thermal gap between the valves and rocker arms is performed during the repair of the cylinder head
Also when there is a knock in the area of the valve cover
With an increased gap, a characteristic ringing sound appears.
With a small gap between the valves and rocker arms, the engine will seem to be “clamped”, or they also say “dumb”.
At the same time, its power and throttle response will be reduced, as well as increased wear of the valve mechanism.
Adjustment is carried out on a cold engine.
Remove the carburetor air filter housing for this:
Loosen the clamp with a screwdriver and remove the crankcase exhaust hose.
We “snap off” five clips, and remove the cover of the air filter housing, take out the filter element.
Loosen the clamp with a screwdriver and remove the corrugated air intake hose.
With a screwdriver, we bend the antennae of the lock washers, and with a 10 key we unscrew the three nuts.
Remove the air filter housing.
Disconnect the crankcase exhaust pipe.
Disconnect the vacuum regulator hose of the ignition distributor sensor
Using a 10 socket wrench, we unscrew the six bolts of the block head cover
Remove the cover
Remove the gasket.
Set the piston of the first cylinder to TDC.
To do this, turn the crankshaft so that the third mark on the pulley aligns with the lug on the cover of the timing sprockets.
After that, remove the distributor cap and check that the slider is in the contact position of the 1st cylinder. Otherwise, rotate the crankshaft one revolution.
Both valves of the first cylinder must be closed. Rocker arms sway freely.
With a 14 key, loosen the lock nut of the adjusting screw and unscrew the adjusting screw by one or two turns.
Insert a probe between the valve stem and the rocker.
We turn the adjusting screw until the probe moves in the gap with little effort.
Having set the gap, hold the adjusting screw and tighten the locknut and check the gap again.
We adjust the clearances of both valves of the first cylinder.
Then with a special key behind the ratchet:
- Turn the crankshaft half a turn (180°) and adjust the clearances in the valve drive of the 2nd cylinder.
- Turn the crankshaft another half turn (180°) and adjust the clearances in the valve drive of the 4th cylinder.
- Turn the crankshaft another half turn (180°) and adjust the clearances in the valve drive of the 3rd cylinder.
Amount of clearances in the valve drive:
|
Number cylinder |
Valve |
Value gap, mm |
|---|---|---|
|
1 |
Inlet Graduation |
0.40–0.45 0.35–0.40 |
|
2 |
Inlet Graduation |
0.40–0.45 0.40–0.45 |
|
3 |
Inlet Graduation |
0.40–0.45 0.40–0.45 |
|
4 |
Inlet Graduation |
0.40–0.45 0.35–0.40 |
After adjusting the valves, you need to start the engine and after warming up, make a test drive.
Check engine operation in all modes. In case of unsatisfactory operation of the valve mechanism, repeat the clearance check.
