I finally finished replacing the timing chain in my car.

I want to thank Sixto for his immense help and patience in helping me with the task.

I replaced the timing chain, tensioner, cam sprocket and timing chain guide.

1) Remove the cross over pipe

2) Remove the cam cover - ( bolts tighten to 10Nm when replacing)

3) Remove chain tensioner - new one seems to be made of some brass alloy. To prepare the new chain tensioner, place the plunger ( vertical with plunger end ) into a small container of engine oil (10W-30 or 40 works). Push on the tensioner while plunger end is in oil, until it starts to move easily. I had Sixto hold the tensioner while I gently stepped on it. It required about 7 pushes with my foot before the plunger moved easily.

4) It is prudent to replace the plastic timing chain guide that is at the top right ( when facing the engine from the front of the car ). This should be the first task. The reason for this is that the cam sprocket has to come off to R&R the guide. We realised this after we finished replacing the timing chain and cam sprocket. The guide is held on by 2 dowels. One dowel is used as a pivot for the spring tensioner, and the other is just above the vacuum pump. We used the bolt and washer method to remove the dowels. The dowels take a 10mm bolt, same size as the cam cover bolts. It was a job getting those dowels out and back in !!!

5) The cam sprocket goes on in one direction. There is a small hole on the cam sprocket, where a small dowel on the cam shaft fits. Look at the sprocket u r removing and compare it to the one u have. Mark the chain and location of the link on the sprocket. The cam sprocket is held on the camshaft by a 13mm - 12 point bolt. Using a big screw driver, to lock the sprocket, remove the bolt and thick washer. Remove the old sprocket replace with new sprocket. Once again lock sprocket and tighten to 25 Nm. Then tighten the bolt 90 degrees. We marked the bolt with a punch and tightened it until the dot moved a quarter circle.

6) Grind off 1 chain link and punch out 2 metal dowels. Link with new chain and roll chain around until the 2 ends meet. I borrowed a chain crimper from Steven Snellings, a forum member. I must say that u really would be much better off using an MB chain crimper. Thanks Steven!

7) On the 602, the manual says to move flywheel until it is at 0T. Then put on new tensioner and tighten to 80 Nm

8) Put all other parts ( cam cover, spring tensioner, cross over pipe etc )back in place.

Started the car and it sounded good. I used to have some white mist and engine shudders when starting the car cold. That has disappeared.

As GSXR has posted sometime back - MB has a TSB on 93 300D 2.5L - stating that they have defective chains. MB advised replacing the chain, tensioner and sprocket.

It has made a world of difference. I want to once again thank Sixto for all his help and guidance.