Subject: Silencer damaged by bad doughnuts

[C1J1Miller@aol.com]

Phil Payne wrote:
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I replaced the ur-quattro's back box with a stock Audi part on 28/11/97.
I have the invoice in front of me.  As per usual, I also replaced all
the trivial parts - the clamp bolts and nuts, the sealing ring, and
the rubber suspensions.
Sometime during the last four days, both of the suspensions on the rear
silencer have failed.  Part number is 8A0 253 147A on the fiche, on the
parts, and on the invoice.
I always thought they were metal-reinforced.  No sign of anything but
rubber inside these.
The exhaust has been rubbing (with considerable pressure) on the rear
inner CV joint.  This is now highly polished and slightly concave -
fortunately, only the middle section seems affected and the boot is
still intact.  There's a hole in the exhaust pipe almost an inch long
and half an inch wide.
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fred smith replied:
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You probably know this,but in case you don't,the VW aftermarket
guys sell these "figure 8" hangers with bicycle chain imbedded in
the rubber.They cost about $6/8 each. Nice "safety item.
========
The VW chain hangers are not recommended for the audi applications by the
maker due to the weight of the audi exhaust compared to the A1/A2 model VW
exhausts (a few 20-v coupe/90 sedan owners have had them fail; the chain is
not a complete loop, and can pull out of the rubber).  I've seen a variation
on this:  use nylon tie-wraps to partially compress the rubber hanger, and
take up the weight of the exhaust.  The nylon tie keeps the rubber from
stretching to the point of breaking, while leaving the rubber to move and damp
the exhaust motion, and the nylon strap should last forever.
If the exhaust is stainless, sounds like an easy weld repair.  When installing
the exhaust, it is very important to test fit it carefully (loosely tightened
connections) before final tightening; otherwise, you can develop a lot of
torque on the rubber hangers as they try to make the exhaust fit properly.
Best done on a lift.
hth, chris miller, windham nh, c1j1miller@aol.com
'91 200q ==> http://members.aol.com/c1j1miller/index.html