I've had a slight noise coming from my 81 300SD engine since I installed it.
The engine is from a 83 300SD.
The sound it makes is like pedaling a ten speed backwards.
The noise the chain will make going through the derailleur. Real inconsistent no pattern to it but mainly at idle.
Raise the throttle and it goes away.

Ive read the chain stretch threads and have done the one lining the marks up. (About to tackle the 2mm one.)
This gave me 5 degrees , so 3 above Mercedes break in spec.
While the valve cover was off I noticed real light marking on the valve cover above the chain.
This to me indicates the chain is lifting upwards slightly.

Now the Question: is the tensioner slacking at idle or is the chain wore out.

From what I understand the tensioner has a spring that takes up the slack.
Then the ratcheting mechanism should hold this position not relying on the spring.
This to me would prevent the chain from rising on the cam gear.
Some stretch I've read about exceeds what I'm getting without any noted problems.
Owners Adding a offset key to bring it back in specs and go on driving.

Now I need an idea on what I may have and where to take the troubleshooting from here.

Any Ideas ?

Thanks in advance.

__________________


Experience : what you receive 3 seconds after you really needed it !!



86 300SDL 387,000? Motor committed suicide
81 300SD 214,000 "new" 132,000 motor
83 300SD 212,000 parts car
83 300SD 147,000

91 F700 5.9 cummins 5spd eaton 298,000
66 AMC rambler American 2dr auto 108,000
95 Chevy 3/4 ton auto 160,000
03 Toyota 4runner 180,000 wifes