This old V-8 used the metal rails with plastic glued on. I have never seen them fail. I hope they left these when the engine was gone through. I think, but am not sure, that the replacement are the crapy plastic rails. I'd look at the invoice and see if timing chain rails were installed. In either case, I'd think that you should be OK. Just be SURE to have a QUALIFIED Mercedes Tech look at it before purchase.
1992 500E (very soon I hope
1981 280GE SWB
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