300 turbo engine. Slight chain whirr. What to look for? - PeachParts Mercedes-Benz Forum

Motorhead · #1 03-14-2011, 03:55 PM

I am in the middle of getting a '83 turbo engine ready to install in my '77 240. I

have the whole '83 as a donor. The engine runs well but at idle, you hear a little

chain whirr. I have the engine out now and I am going through and servicing and

or replacing things within reason to get it solid before I install it. I have removed

the valve cover, tensioner and checked the main chain rail. It has some groves

in it from the timing chain but not bad. I have a factory 617.952 engine service

manual and it does show how to R&R the rails. The chain doesn't seem

stretched as the cam mark was dead on at TDC. I DO have a new chain but

don't want to replace it unless it is bad.

Is there anything that you guys can come up with to also check? Oil pump

chain?

leathermang · #2 03-14-2011, 04:25 PM

You have the turbo engine manual but have not read it.... or you would not have made that statement about the cam mark.

Motorhead · #3 03-14-2011, 07:47 PM

Quote:

Originally Posted by leathermang

You have the turbo engine manual but have not read it.... or you would not have made that statement about the cam mark.

You know, I have run into you before on this site. You don't know what I have read or NOT read.
I know about using the offset keys to adjust valve timing.
If you don't have any POSITIVE input to the questions I am asking then keep your damn remarks to yourself.

snookwhaler · #4 03-14-2011, 08:07 PM

What he was saying is this....

You did measure your timing chain stretch using the "valve lift method".... Right?

This is the method that MB specifies.

leathermang · #5 03-14-2011, 10:03 PM

The FSM says specifically that the cam mark is only for initial building of the engine. It is not accurate in terms of measuring chain elongation.
As Snookwhaler said... .the 2 mm movement of the number one valve is specified as the method for this procedure.