[urq] A new urQ owner, and a big problem...

[Buchholz, Steven]

The Audi 5-cylinder turbocharged engines are static interference engines
... i.e. yes, even if the timing belt breaks at low RPM you will likely
have valvetrain damage.  Obviously the "shop" to which this car was
taken is not very familiar with the mid '80's Audi models.  There's no
way I'd recommend going through the effort to pop another timing belt on
there to see what happens ... in fact, if he is truly seeing -0-
compression on all cylinders, I'd say he'd have a reasonable case that
reinstalling the timing belt caused the majority of the damage.  Usually
the camshaft stops pretty quickly when the belt snaps ... although the
comment that the crank pulley was loose might do the same thing.  If
this is indeed the case, the owner should investigate whether there's
any damage to the indexing mechanism on the crankshaft and pulley.  

Could the A/C Compressor have induced the problem?  I suppose there is
some possibility of this, but I'd be pretty skeptical myself ... 

Steve B
San Jose, CA (USA)
> 
> Today, I called to invite him at UPG-05. Bad news, the car is at the
shop,
> with a no-compression engine.
> 
> He said he brought the car 1 month ago to have the AC system filled
with
> R134a. The conversion went well, AC functional but not very cold
(which is
> normal for a converted system), and on the way home he stopped for
gas,
> engine working normally. When he tried to restart, no start but engine
> cranked faster than usual which probably means the TB has snapped. He
> called the shop who said "floor it and keep cranking, these engines
have
> hot start problem", which we know is true.
> He had the car towed at the shop who said "the previous owner didn't
put
> Loctite on the crankshaft bolt, so it moved and the TB broke".
> 
> Now, after replacing the TB, the engine has simply no compression. The
shop
> did look into the cylinder and said "must take the head off, something
is
> broken..."
> 
> End of story for now.
> 
> Questions :
> is it possible that the "new" load of the AC compressor managed to
moved
> the damper and break the TB ?
> Are this (stock WX) engine an interference engine at very low RPMs ?
> What can cause the no-compression ?
> 
> It's a shame since the owner wanted to keep this car in a stock and
perfect
> shape, hence the reason he had the AC work in the first place.