164 Exhaust leak

[Lawrence Leong <leongccl@domain.elided>]

You've all heard of the Alfa-powered boats, well, my 164TS is 
now a boat too!  (and I don't mean the size :-) ).  There 
are a few other problems, but this loud sound is the most urgent
(and embarassing).

A visual inspection suggests that the cat con has sprung a 
rather largish hole, and rattles at above 3500 rpms.  I suspect 
it's shot, but I still welcome comments.  (I stuffed a rag into
the tail pipe, then felt for the exhaust gas leak.  There was no
change in rpm when I stuffed the rag in - that's bad!)

I assume the first device after the headers is the cat con.

The "cover" has given way and exhaust gas now comes out 
all round the rear end of the cat con.  (by cover, I mean the 
end cap which flares out to the pipe connecting the cat con to 
the muffler.  Now, there's a gap approx 180deg along the 
circumference where it's crimped to the rest of the cat con 
body).

The PO did some exhaust welding in Jul last year.  I suspect 
it's related to the current problem.

My options are either:
  a.  weld it up again, prepare for a welding job every 6-8 months.
  b.  change the cat con

My preference is for (b), and this is where I need inputs.

The cat con is welded to the headers/manifold.  When you change
the cat con, do you change the headers too?  Or do you cut off
the cat con and weld in a new one?

Either way, any gotchas or things to look out for?

Also, anyone has a good 164TS cat con for sale?
The p/n is "164.20.09.009.00".  

If the cat con is the 2nd device, it is 
164.20.09.013.00, but I suspect this is the muffler.


Cheers
Lawrence
(Yeah, I could fit a test pipe ;-) but I won't)



92 164 2.0 TS
86 33 1.5 QV (Sold, but spares & manual still available!)

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