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Re: One valve down. Is it safe to drive ? (for a while ...).
- To: firstname.lastname@example.org
- Subject: Re: One valve down. Is it safe to drive ? (for a while ...).
- From: email@example.com (Steven Buchholz)
- Date: Wed, 16 Nov 94 17:36:20 PST
- Reply-To: quattro
- Sender: quattro-owner
There has been a lot of talk on this one, but I haven't seen anyone address
the original question ... should you drive a car if you know that a valve is
bent? Personally, I would say NO! ... but what more could happen? The bent
valve stem could ream the valve guide ... But would you replace the valve
guide on a bent valve case as a matter of course? The valve will be hit-
ting the seat funny and could damage it. You don't know if it is an intake
or exhaust valve, and you are doing nothing to prevent ignition of the mix-
ture in the cylinder. If it were an intake valve couldn't you have the
exhaust gasses fed into the intake manifold? I know that some turbos have
sodium-filled exhaust valves ... BOY would that be exciting if you just
happened to crack one of them open in a running engine! Was the piston
damaged when the valve hit it? (This could happen if the engine was running
at higher revs when the belt broke.) No, I would not drive a car knowing
that it has a bent valve stem!
The other issue is ... is it possible that no valve stems were bent? As
I recall the car is a 5K turbo. I believe the 5KT motor has the same
piston design as the TQCoupe. I know for a fact that the valves will
contact the pistons if the cam isn't turning while the crank is. The
pistons are not relieved where the valves would meet them. I'll bet
that something touched something else.
All of the above is my opinion based on my understanding of internal
combustion engines and Audis. Am I overreacting? Is it a case where
simply unplugging the spark plug on the offending cylinder would allow
use of the car at reduced capacity?
'88 5000CSQ Wagon
'83 TQCoupe (yes ... I've pulled the head off of this one!)
'78 Fox GTI