muffler autopsy

[Dave C]

Dan,
Maybe it would be worth considering a simple repair of the muffler on the
car.  Copied below is a post I sent to the Q-list a couple of years ago
(12/18/98 I think) ...describing my investigation of a similar small hole
in the muffler.
----------------
Dave C.


I recently replaced the middle (front) muffler on my 87 5ks at 127k miles.
It had a small hole and was noisy so I thought it was the thing to do.
Part of my concern was that the insides might be disintegrating and causing
problems.  In the name of science I decided to take a peek inside the old
muffler to see what it is made of.  I opened it up with a cut-off wheel on
an angle grinder.

This muffler consists of a straight thru perforated pipe wrapped in steel
wool 1 cm thick.  There are two cavities and one is stuffed with some kind
of insulation which looked a little tired in spots.  The other is empty
except for the 1 cm thick steel wool on the pipe. There was no serious
looking corrosion on the inside except for the hole which was at the lowest
spot, where condensation would have collected.  It appears that I could
have welded this crack and the muffler would have lasted another twelve
years.  There is a layer of thin sheetmetal covering the outside of the
muffler which was half rotted off, but I believe it only served a cosmetic
purpose.  I could have torn it off entirely with no effect on the function.
 The inner primary layer of metal is >much< thicker than the outer one.

Overall I am very impressed with the quality of this muffler.  If I were
doing it over I'd probably have welded the hole shut and got more
additional years of service out of the old one than many of the new
aftermarket products would provide.

Dave C.