another 240 vibration noise found... but what's the cure?

I replaced all three motor mounts today (two motor mounts and the
tranny mount to be specific). While under there I found the last(?)
source of the vibration rattle. The parallel pair of 90 degree bent
header pipes that goes from the exhaust manifold towards the catalytic
convertor seems to be double walled. When I strike it I can hear what
sounds like a spring rattling inside. I assume that this is a
double-walled pipe, and the inside pipe is either broken loose from
some welkds, poorly executed, or rusting through(?). Anyone deal with
this sort of thing before? I have some ideas, but am awaiting more
enlightened opinions.




__ __
Randy & \ \/ /alerie's
\__/olvos
'90 245 Estate - '93 965 Estate
"Shelby" & "Kate"

 

The original pipes had a stainless steel cladding with some insulation
behind it to try to keep the heat in the exhaust gases, so the catalytic
convertor would warm up and start working sooner after a cold start.
When they start rattling find where they're loose and insert a small
sheet metal screw between the 2 pieces of metal to put some tension on
the loose joint.

--
Mike F.
Thornhill (near Toronto), Ont.

Replace tt with t (twice!) and remove parentheses to email me directly.
(But I check the newsgroup more often than this email address.)

 

That is exactly what I was thinking- So are they 3 layers- an
insulation sandwich (as it were)? It sounds like they are rattling
along most of their entire length, but two or three well-placed
screws might do it..? About 3/16" or so you think?

__ __
Randy & \ \/ /alerie's
\__/olvos
'90 245 Estate - '93 965 Estate
"Shelby" & "Kate"

 

What I use depends on what I have on hand and the size of the gap.
Whatever fits in tightly enough to stay.

--
Mike F.
Thornhill (near Toronto), Ont.

Replace tt with t (twice!) and remove parentheses to email me directly.
(But I check the newsgroup more often than this email address.)