MY 1990 SL HAS BROKEN ( PLASTIC) GUIDES . My son , a budding mechanic has dismantled everything that we can see to get to the chain and now e are looking at it wondering what we do next. we have fished out the broken bits of black plastic, but how do we now know what piece needs replacing and who do we do it? it is not obvious.

I am not sure about a 1990 model(I think it's a m119 motor), but on the older v-8 models when a timing chain rail broke it tended to bend the valves on the left side head. I would remove both valve covers and check for damage. You will need a crimp tool to crimp the master link on the new chain. You might check with a shop for estimate on repair. By the time you add up parts, tools, supplies, pepto-bismol(sic), and asprin you might want to have a qualified shop finish the job for you.

do you have the manual for the car? That would have been an excellent first step;-)

I agree w/ the post above, you will be Very lucky if you didn't bend a valve or two in the process of breaking the guide.

I'd wager you will need to pull all the accesories off the front of the motor to gain access to the guide rail pins that hold them in place.

Again, the manual would be the way to go.

jonathan

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Jonathan Hodgman
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When I needed to change the timing chain and guide rails on my 116 engine I subscribed to www.pindelski.com. Though I had the CD manual, the pics and hints on this site were well worth the $30 I paid for the yearly subscription. Timing chain slap led me to change the timing chain. I discovered 2 broken guide rails but no damage to the valves, so dont get discouraged.

One of the things you can do is order the new parts - you're going to need them no matter what. They will often shed some light on what's going on. Get a manual somewhere - AllData for example. You should take the oil pan off - probably find some more plastic crumbs there. If plastic parts made it to the oil pan you will probably find some stuck up in the oil pump intake pipe. This needs to be cleaned out - not too hard once you find it.

wow, thanks all of you for your response and advise. This is the first time I have posted and I was supprised to get any thing.