RE: Loud mettalic tapping from top of engine.

["Iain Atkinson" <iain.atkinson@virgin.net>]

Thanks Dan, pleased for you that yours went away.

I drove it again today, all ok when cold but when the oil temp got up to 100
deg or more it came back. I have today ordered a new set of lifters and am
going to do the timing belt at the same time. Time for some surgery on the
top end. I got a mail also from friend of mine in Germany here is what he
thinks:
"I know this prob very well, the real reason is that the distance between
hydraulic lifters and alloy head has became to big, to much oil is flowing
through between the gap and for that the oil pressure in the lifters is to
less.
Without the right oil pressure the lifters cannot fit the right high, the
camshaft is hitting the lifters hard due to the too big distance
camshaft/lifter.  Very hard to repair that, the only thing is to buy a new
head, yes its true!  What a friend of mine did, he raised the oil pressure!
After that the engine was like new, but nobody knows that is happening with
an higher oil pressure exactly"


Food for thought......

I will be letting the list know how I get on.

Regards
Iain


-----Original Message-----
From:	owner-quattro@audifans.com [mailto:owner-quattro@audifans.com] On
Behalf Of Daniel Hussey
Sent:	14 November 1999 17:12
To:	iain.atkinson@virgin.net; quattro list
Subject:	RE: Loud mettalic tapping from top of engine.

> Hi all
>
> Nasty problem occurs this afternoon, I come of the dual carriageway having
> had a bit of a blast and I hear this loud mettalic tapping noise from the
> top of the engine. It happens most when you rev the car and the rev's drop
> back again. It sounds like a much louder version of hydraulic lifter
rattle
> (this almost like someone is tapping the cam cover with a small hammer),
> engine runs fine other than this.
>

Hi Ian,  I had the exact same noise you describe on my 200TQ one time.   It
was very loud and would speed up as engine revs sped up.  I was not very
comfortable driving it, figuring it was a bad valve somethingorother, but I
was late for a study session and drove to my friends house (stupidly?) just
a few minutes away.  Could hear all this inside the car and over modified
exhaust!

Well, ... and this is the wierd part... I was complaning the whole time
saying that this was it.  The engine was surely going to have to come apart
now as something was seriously wrong, etc, etc, etc.  Car drove ok, but was
easy on the revs and drove it home that night....  the noise was still
there, but was much quieter and less noticable.  Next time I drove the car,
the noise was gone completely and has never returned again (been months and
about 15K miles).

So, my advice is be carefull with it, but maybee drive it a little bit more
and see if it goes away.  Mine did.  BTW, Anyone out there know what it
was???  Was surely not lifters.  I've never heard them get that loud and I
think they were improved in the 200's as I have not had a problem with them
at all.  It sounded more like a valve wrap!  I don't think it was a crank
bearing as Huw suggested though as it most definately was coming from the
top of the engine, but then again, I really don't know.  Just glad it's gone
now and I didn't have to rebuild the motor at a $$$$ cost to me!  :)

Later,
Dan