Timing Chain: Service and Repair

Changing The Timing Chain (In Situ)

To remove (in car)
1. Rinse the car and remove the belt circuit cover.
2. Lower the car and remove upper engine cover.
1. Remove the ignition discharge module and spark plugs.
4. Detach the crankshaft ventilation pipe and hose. Cut the cable tie holding the non-return valve. Unplug the boost pressure control valve and remove the camshaft cover.
2. The the crankshaft clockwise until the crankshaft and camshafts are aligned with their setting marks.





3. Check chain wear by removing the chain tensioner plug complete with spring and locating pin, and remove the chain tensioner without changing the position of the piston.
The protruding part of the chain tensioner must not be longer than 15 mm. If it is, the chain must be changed.





4. Check the wear on chain sprockets and chain guide.
Chain guide wear must not be so great that the chain acts on the surface between the outer tracks.
If the surface between the outer tracks shows signs of wear, they must also be replaced and the chain changed in the usual manner.

To fit (in car)
1. Stuff a cloth in the area round the chain and also secure the chain with cable ties on both sides.





2. Open the chain by pressing out a link using Toolkit for timing chain replacement 83 94 637, and then removing the link with a pair of pliers
3. Couple together the new chain with the old one using Toolkit for timing chain replacement 83 94 660. Take care so the chain does not fall down!





4. Make sure that the new chain runs over the camshaft sprocket on the inlet side and fasten the end of the old chain.





5. Fit Toolkit for timing chain replacement 83 94 652 and remove the cloth and cable ties.
6. With the old chain in your hand and the new one resting over your hand, carefully feed the new chain over the sprocket as a helper turns the belt pulley round.

IMPORTANT: Be sure to keep the old chain under tension as it is fed forward. It might otherwise fold itself double down at the crankshaft.

7. When the new chain has been fed forward to such an extent that only a few links still remain on the inlet side's camshaft sprocket, cover the area round the chain with a cloth once again. Remove the chain link and the old chain.





8. Connect the ends of the new chain together with a chain link and pull the chain round until the link is midway between the shanks of the chain support.





9. Remove the chain link and fit a new chain lock.
Check that the inserts marked 2 are mounted in the tool. Then place the chain link's plate in the tool and align it over the link on the chain.
Press the plate in place with a force of 10 Nm (7 ft. lbs.).





10. Reverse the insert in the tool and position the tool with the V notch directly over one of the shanks of the link.
Rivet the shanks with a force of 15 Nm (11 ft. lbs.). Repeat on the other side.
11. Check the riveting by checking the diameter of the compressed shank with a vernier caliper. Correct dimension is 3.4 - 3.6 mm.
12. Remove the cloth and shank support.





13. Fit the chain tensioner.
Tightening torque 63 Nm.
Fit plug, tighten to 22 Nm.
14. Turn the engine over one revolution and check the 0 marks of the camshafts and crankshaft.
15. Fit the spark plugs, camshaft cover and ignition discharge module.