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Head bolts - do not reuse!
In message <350AA182.788F4F18@MCIONE.com> four.rings@MCIONE.com writes:
> I was abut to reuse the head bolts on my 200. Bentley explicitly allows
> to reuse the bolts on the 3B engine and does not say anything about the
> MC engine. I figured if a more stressed 3B does not break the once used
> head bolts, the MC is even less likely to do so.
> The new OEM bolt was right on the spec: M11x1.5x98mm.
> The old one was 3mm longer!!!
> Folks, don't listen to Bentley in this issue. If you pull the head -
> install new head bolts!
There are three takes on this; technical, practical and financial.
Yes, the head bolts can be re-used _once_. The non-elastic stretch that occurs
on fitting can be tolerated exactly _twice_ by any given OEM bolt. The reason
for this (according to an engine designer) is that you might have to remove and
replace the head _IN_ _AN_ _EMERGENCY_ when there are no spares available.
No mechanism has been agreed for marking bolts that have already been re-used.
Perhaps the bolts in your engine have already been re-used? So - to paraphrase
Clint Eastwood -just how lucky do you feel today?
They cost _peanuts_. I know there are half a dozen of so Qlisters for whom
this is a non-trivial consideration, and for them I have sympathy. More than
you might imagine, just at the moment! But for the others - $3 (tops) times 12?
UK Audi [ur-]quattro Owners Club