 
     |
| Dumb Muffler Quesrion (Page 1/1) |
|
PipSqueek
|
NOV 04, 05:23 PM
|
|
I think we might have an exhaust leak on our 87 GT. Doing some investigating we saw this hole in the muffler. Since it’s perfectly round I thought this might just be how it was made. Do I need to start looking for a muffler replacement?
|
|
|
|
IMSA GT
|
NOV 04, 06:13 PM
|
|
That hole is normal. It allows excess water to drain out of the muffler.
Why do you think you have an exhaust leak? Is the exhaust a different tone?[This message has been edited by IMSA GT (edited 11-04-2022).]
|
|
|
|
PipSqueek
|
NOV 04, 06:15 PM
|
|
|
|
|
PipSqueek
|
NOV 04, 08:57 PM
|
|
|
We have a sewing machine type sound and the exhaust is louder than it used to be. We recently started getting skips in the engine.
|
|
|
|
IMSA GT
|
NOV 04, 09:10 PM
|
|
Listen around the exhaust headers. It is common for the gaskets to fail as well as the stock headers to crack and leak. They will usually develop cracks around the factory welds where they bolt to the heads.
This is a set that someone had for sale a while back. You can clearly see the repair welds on both.
 [This message has been edited by IMSA GT (edited 11-04-2022).]
|
|
|
|
cvxjet
|
NOV 04, 10:38 PM
|
|
A) Use a piece of heater hose as a stethoscope to pin-point the noise.
B) I have had some strange noises coming from the exhaust- and the engine was running a bit odd- Took the exhaust off and shook it (Isolating the mounting springs) and heard a lot of rattling- cut a hole in the muffler and took out a bunch Cat chunks...Then had a friend weld it back up.
C) Later, I had some more rattling- took the exhaust off- but did not want to cut it open again, so, looking at the design of the muffler baffles, I started shaking the exhaust, so that the pieces would "Hop" over the end of the pipes and then fall out- This actually worked very well- I did find that there was a large piece lodged against a weld seem in the pipe from the Cat to the muffler- hit the pipe with a large hammer a few times to dislodge/break up that piece (Success) Note; I would not hit the exhaust with the Cat attached- I actually have the Cat bolted on with a flange so I can remove it if the engine goes out of tune (I have a straight pipe I can install)
|
|
|
|
PipSqueek
|
NOV 06, 07:34 AM
|
|
|
We sprayed soapy water on the manifolds, put rags in three of the tail pipes and then blew air into the fourth tail pipe. We got bubbles on both the front and back manifolds at the connections. It looks like the gaskets need to be replaced. (This is a v6 BTW). The front exhaust manifold doesn’t look like it would be too difficult to remove but the back one seems like it would be a higher pain.
|
|
|
|
IMSA GT
|
NOV 06, 10:39 AM
|
|
|
Yes, the front manifold may be quite a pain to remove. You may be able to remove the decklid, remove the dogbone mount, and use a ratchet tie to tilt the motor towards the rear of the car for a little more working room. Some people break off the bolts when trying to remove them. Just use a lot of penetrating oil and hope for the best. Glad you found the source of the noise. Small leaks like that can be very irritating because it can give you a false impression that a lifter is collapsing with the "ticking" noise. [This message has been edited by IMSA GT (edited 11-06-2022).]
|
|
|
|
PipSqueek
|
NOV 06, 11:01 AM
|
|
|
Thank you for the advice!
|
|
|
