RE: BAD grinding sound.....HELP!

[Marc Gallagher <mgallagher@Langan.com>]

For those interested here's the scoop from the best I can surmise:

1)  The tensioner pulley for the s/c cracked in two (a ring separated),
leaving the 1/3 of the belt next to the engine unsupported as it went over
the pulley.

2)  This caused an eccentricity in the load on the belt, causing the belt to
be tight on the outside of the water pump pulley and loose (relatively) on
the inner side.

3)  As a result of the uneven load, the rubber (?) "tire" on the water pump
pulley actually shifted on the metal "hub".  The shifted "tire" was then
rubbing against the unibody (not much clearance if you have not seen it).

4)  So, I need a new water pump pulley ($25) and s/c belt.  I already have a
new s/c pulley that is machined aluminum instead of plastic.

5)  Unfortunately, I had to strip off the s/c and am now back to stock until
I get the s/c belt and the energy to reinstall everything  :-(

m-

> -----Original Message-----
> From:	Marc Gallagher 
> Sent:	Wednesday, December 12, 2001 10:07 PM
> To:	'jettaglx@igtc.com'; 'list@gti-vr6.net'
> Subject:	BAD grinding sound.....HELP!
> 
> Hi all,
> 
> Here's the story:
> 
> 97 glx, 67,000 miles, z-eng s/c.
> 
> On the drive home today on Route 78 in Jersey, down shifted to 4th doing
> about 70 to get in the passing lane.  As I let off the gas to shift back
> to 5th and start to let the clutch out I get a semi-loud clunk.  hmmm
> 
> Nothing for another 20 miles.  Then down shifting on the off ramp to 287,
> while letting the clutch out a mutch more pronounced thumping sound.
> Sounded something like if you stick a piece of wood in a fan while it is
> ont.  Real fast, repeated thumping.  Not a gear grinding sound.  At first
> I thought it was something stuck int eh wheel well rubbing the tire as I
> turned ont he ramp.  I now hypothesize (sp?) that once the engine/fly
> wheel/clutch was back to cruising speed the thunping stopped.
> 
> After checking the wheel well for a foreign (or broken) object, I tried to
> create the sound in the driveway and was somewhat successful.  It seems to
> happen when releasing the clutch, before the clutch/fly
> wheel/engine/tranny all get sync'd together.  Again, it is a deep, rapid
> thumping,  Not at all pleasent.
> 
> Any ideas before I schlep it over to the shop?
> 
> cheers,
> marc