Updated chain tensioner - IMS to Crank
 

Okay here we go again

Just went pick up the most up to date chain tensioner for the IMS to crank chain. It's the one with the external spring. I was told that this spring type is not compatible with my early 2000 986S engine (dual row IMS bearing) as I have a roller chain type IMS drive and not the newer tooth drive chain.

These changes ( tooth chain ) were instituted for engine numbers M96.21 67 1 02086 onward. Apparently they could tell from my VIN that mine was an earlier engine (not sure I trust vin based engine component listings where is the engine number again?). I believe this is covered in a bulletin 8/00 1551.

So I belive some of you have put the newer style tensioner in irrespective of engine series and earlier chain type . Is it okay? Any issues? Did it help to chain rattle on startup?

I installed all 3 new tensioners in my 2001 earlier this year, though because the car was built in Feb 2001, I think the engine would have been assembled late 2000 and then transported to Finland for co-assembly to the chassis. It has the dual row IMS bearing & later style toothed "Hi-Vo" type chains fitted, as my engine is #67 1 07779.
The start up rattle from cold has always been with the car, especially after sitting for several days, and sometimes even when hot after sitting for a couple of hours after a run. But since the new tensioners were fitted, the rattle has reduced significantly (~50%) from cold and has ceased completely from hot. Which one of the tensioner(s) was responsible for the rattle is difficult to tell, but I'm pleased I replaced all of them - when one bleeds down, the others will surely follow.

Yes 2001 onward is what was mentioned...so you are good. Just trying trying to comprehend the incompatibility.... why?

See you posting same subject another forum. The TSB explains it.

I have a 2000 S with 75,000 miles. Is a there a general rule as to when chain tensioners need replacing and a general price for parts and labor?
Thanks

No general rule that I know of. I would say that at 75 they are going to be gummed and pretty lazy but that is just a guess.

Yes I hope to get responses from those who know the reason for the compatibility and those who might have gone against it......to good effect. Did anyone answer..?

Is there more spring load with external spring model? Does the tooth chain support more tension load than the roller and is this how the rattle is stopped?

I have an early base 2000 with dual row IMSB and had chain tensioners done last year along with chains, guides, IMSB, AOS, clutch, water pump. I have had no problems, no rattling. I did not know there was supposed to be an incompatibility- was not told about it.

Thanks, jaykay.Any idea of a general price for parts and labor to do new tensioners?