What is the recommended mileage/years to update the timing chain and related pieces on the 450SL engines? Do these engines use metal or plastic guides?

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1986 560 SEL (159K miles)

Same recommendations as here:
Timing chain on a 420 SEL

Real early motors has rubber over aluminum rails. They have all been replaced by the POS plastic ones.

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Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician

Real early motors have rubber over aluminum rails.
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Would a 1973 450 SL be considered a "real early motor"?

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1986 560 SEL (159K miles)

Might be, but if its ever been worked on or if they are worn the POS plastic are the current MB replacements.

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Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician

Just wondering,

With the rather short life expectancy of these cheesey plastic guides and the resulting catastrophic damage from their failure why hasn't an aftermarket manufacturer come up with a better replacement?

The original rubber faced aluminum ones sounded like a much, much better design.

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Chas

Had a 380SL, 450SL, 380SEL, 420SEL, 500SEL

Got a Euro 500SEC right now.

I once had a 72 350SL come through the shop with a high pitched squeel when it ran. (this one had the 117 engine in it by the way) It turned out to be the timing chain had worn all the way through the rubber guide and was scraping on the guide It filled the front of the engine full of shavings Had to pull the engine and take it all apart to clean, and also did a valve job too.. Boy that was a close one.. I am sure it would have broke the chain soon and what a mess that would have been!!

Rob...