Valve Clearance: Adjustments

Checking and adjusting the valve clearance

Note: Always check or adjust the valve clearance with the engine cold (approx. 20° C). Check by inserting the feeler gauge between the end face of the stem and the cap of the valve adjusting screw.

If the spark plugs are not removed when the valves are adjusted, the engine must only be rotated at the bottom pulley or at the internal multi-tooth end of the generator shaft.

Valve clearance with the engine cold:






Intake: 0.1 mm
Exhaust: 0.1 mm

The clearance is adjusted according to the firing order 1 - 6 - 2 - 4 - 3 - 5. The piston for the respective cylinder must be in top dead center of the compression stroke as both valves are then closed. The TDC marking for each cylinder can be found on the pulley.

Cylinder Designation:

1. Cylinder 1 is the first to be adjusted. For this, turn the crankshaft to the right with the V-belt pulley until both valves of the cylinder are closed (overlapping cylinder 4) or until the distributor arm is aligned with the marking on the distributor housing. The TDC marking (Z1) on the pulley must be level with the crankcase seam or the locating mark on the blower housing.

TDC Mark:

Distributor Marking, Cylinder 1:

2. Check the valve clearance with P 213 b; if necessary, undo the hexagon nut on the adjusting screw and correct the valve clearance by turning the adjusting screw with a suitable screwdriver, hold the adjusting screw firmly and tighten the counternut






3. Check the clearance again.
4. Now, continue turning the crankshaft clockwise with the pulley as far as the next marking (120°). The valves for cylinder 6 can be adjusted in this position.
5. Turn the crankshaft to the next marking (120°) to bring cylinder 2 to firing point.
6. Repeat this procedure accordingly to adjust the other valves (cylinders 4, 3 and 5).
7. Always replace the valve-cover seals and the self-locking nuts.
Tightening torque 9.7 Nm (7 ft lb)

The following assembly operations must be carried out before adjusting valves:

Assembly work from above:

1. Remove the rear wheels
2. If the vehicle is fitted with a catalytic converter, separate the plug connection to the Lambda probe, removing the hot-air blower beforehand.










3. Push the probe cable with rubber grommet downwards through the engine paneling on the left-hand side.
4. Undo the front fastening screws on the engine side paneling beforehand.
(4 screws M 6 x 10)


Assembly work from below:

1. Remove the engine guard.
2. Remove the exhaust system complete (except heat exchanger).
3. Remove the side encapsulation panels from the engine.
4. Undo the side engine paneling.
5. Disconnect the spark plug sockets from the upper and lower ignition circuits.
6. Remove the valve covers for intake and exhaust.

Note: The clearance for intake and exhaust valves can now be checked and/or adjusted from below.






Installation of ignition leads on exhaust valve covers differs, so that valve covers must not be mixed up when installed.

Check for perfect seating of spark plug connectors and routing of ignition leads.

Left Side Cyl. 1-3:

Right Side Cyl. 4-6: