Vehicle: 86 420SEL, 90,000 miles

Well folks I am knee deep in the process of replacing the timing chain. The plan is to replace chain, tensioner and guide rails, cam oiler kit.

It appears I have no visible chain stretch. Timing marks all line up. The question I have is do I need to replace the chain and tensioner? Should I leave it alone and just replace the guides? Any thought?

Thanks,

Joe

the double row chains go on forever, well past 90K.

If the marks are still close to being aligned..not more than 4 deg on the drivers side...thei I would replace the upper guide rails & the tensioner!

USE only a factory tensioner, the aftermarket ones do NOT have the same internals & will fail way too early.

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Thanks for the info. Another question. Do I have to remove the cam sprocket to remove the left side (drivers) chain rails. I have been unable to get both chain rails out without removing the sprocket. I have the CD version of the service manual and the procedure does not specify removing the chain sprocket. Looks like - by the service procedure - that they slip out. Am I missing something?

Thanks,

Joe

If the LH rails can BOTH be removed AND installed without removing the gear, I'd like to see how. Both times I've done this, I removed the tensioner and cam followers on the RH side to relieve tension, got both LH plastic parts OUT, but couldn't get both IN without removing the gear.

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86 560SL
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85 380SL
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http://juliepalooza.8m.com/sl/mercedes.htm

Thanks Stife. Will remove left hand gear and be done with it. Can't see how to do it otherwise.

Thanks to all for help.

Joe