300D 6-cyl 603 series engine, 1986 W124 with 5-speed trans
220k miles

I'm hearing a new noise like valve tapping at around 3000 rpm, but not at idle, and more noisy when off load. Is it likely that the culprit is the timing-chain ?

I plan to replace it anyway since it's overdue. Any special advice on this procedure ?

Will I need a chain-pin removal tool ?

Thanks In Advance.
Michael

__________________
Michael H
1986 300D W124 5-spd manual 250k miles

The chain pin removal tool is called a "side grinder" - just grind the heads of the rivets off and push the link through. Make sure everything is at TDC on the comp stroke of #1 prior to releasing it. Also, make sure that you have the chain secure to the camshaft sprocket before cutting it. This is how I did it. As you can see if you look closely the new chain is in and the old is out.



I would recommend to replace the tensioner while doing this job.
Take your time and I would suggest ALWAYS KEEP THE CHAIN IN CONTACT WITH THE PROPER "TOOTH" OF THE CAM SPROCKET. I did it using the tie wraps as shown.
Do a search on timing chain and review them.

__________________
Jim