170k is getting up there in miles (if it's true miles, VDO odometers always break), if the car's a keeper... I'd just pull the heads.

I wasted my time doing stem seals on my M103 and the guides are well worn past the point of stem seals helping.

Yes, I'm sure it's not what you want to hear... but it's what I'd do since stem seals are big labor on the V8s (and probably not the only issue considering the chain was stretched TEN DEGREES and you had broken guides... that points to me serious lack of upkeep over the years prior to your purchase).

I agree with donbryce, you get the "while I'm in here" deal... your miles/age means most everything rubber needs to be replaced. Breather tubes, injector seals, fuel distributor boot, intake manifold seals, etc

Check ebay for reman heads, you may get a steal on a set.

I have all the tools to pull the cams and heads if you want to borrow them.



My 2¢

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I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]