Valve Guide Seal: Service and Repair

Valve gear (in car)
To remove





1. Unplug the connectors and remove the ignition discharge module and spark plugs. Undo the bolt securing the crankcase breather pipe on the camshaft cover and remove the nipple for crankcase ventilation and vacuum from the camshaft cover. Remove the camshaft cover.





2. Rotate the crankshaft to the 0 mark, remove the chain tensioner and dismantle the camshafts. Cover the space for the sprockets and timing chain to prevent valve cones and seals from dropping into it.

IMPORTANT: Keep all dismantled valve gear parts in valve stand 83 93 787.

3. Lift out the tappets, using magnetic tool 83 91 401.
4. protective collards 83 93 746 around the valve springs to protect the tappet sliding surfaces. Note the position of the collar.





5. Rotate the crankshaft until the piston in the cylinder concerned is at top dead center. Lock the engine using flywheel locking segment 83 94 868 and fit the air nipple for spark plug hole 83 94 173. Connect the compressed air and pressurize the piston and valves.





6. Press down the valve disc with Valve spring compressor83 95 246 and remove the valve cones.
7. Lift out the spring cap and valve spring and remove the washer with valve guide seal using pliers for removing valve guide seals 83 94 157.

To fit





1. Fit the washer with valve seal using pliers for removing valve Guide seals 83 94 157.
2. Fit the spring and spring cap and fit the valve cones in the spring cap's groove.





3. Disconnect the compressed air, remove the air nipple and the flywheel locking segment.
4. Turn the crankshaft to the 0 marking and then 45°.





5. Remove the protective sleeves and fit the valve tappets.
6. Fit the camshafts and bearing caps, starting where the cams point downwards and press on the tappets. Bearing caps marked 1-5 for the inlet side, 6-10 for the exhaust side.
Tightening torque 15 Nm (11 ft. lbs.).

IMPORTANT: The black bolts have an oilway and should be fitted on the spark plug side.

7. Line up the marks on the camshaft with their timing marks and turn the crankshaft back to the 0 mark.





8. Fit the camshaft sprockets and chain. Start with the inlet side camshaft. Do not tighten the bolts yet.
9. Prepare the chain tensioner for fitting by pressing down the catch and pushing in the chain tensioner.
10. Fit the chain tensioner, using a 27 mm socket.
Tightening torque 63 Nm (47 ft. lbs.).
11. Fit the chain tensioner plug with push rod and spring.
Tightening torque 22 Nm (16 ft. lbs.).
12. Check that the chain runs correctly on the chain guides. Rotate the crankshaft two turns and check the settings of the flywheel and camshafts. Tighten the camshaft sprocket bolts.
Tightening torque 63 Nm (47 ft. lbs.).
13. Clean the sealing surface of the camshaft cover with benzine.
14. Apply a soap solution to the opening in the camshaft cover and fit the cover, starting at the opening end. Then continue all the way round, on both the inside and outside.
Tightening torque 15 Nm (11 ft. lbs.).





15. Fit the nipple for crankcase ventilation and vacuum for the camshaft cover. Refit the bolt securing the crankcase breather pipe on the camshaft cover.
16. Fit the spark plugs.
Tightening torque 28 Nm (21 ft. lbs.).
17. Fit the ignition discharge module.
Tightening torque 11 Nm (8 ft. lbs.).
18. Plug in the ignition discharge module's connector.