Stingray454
09-09-2005, 08:58 AM
I just put a new Flowmaster crossover pipe in my truck last weekend. I got new exhaust "donut" gaskets for it from the dealer. Unfortunately, exhaust is leaking past the gaskets on both sides now. Not a lot, but a little - enough to sound like crap (like air whooshing sound from an exhaust leak).
I noticed when I got the gaskets, they both had this metal ring inside them, and sticking out about a 1/4" from the flat portion of the gasket where it should stick in the exhaust manifold flange. This metal ring looks exactly like a piece of exhaust pipe with the gasket material attached to it. I thought maybe this metal ring would fit inside the exhaust manifold opening, but it is too wide of a diameter, so it would only fit on the outside of the lip of the exhaust manifold opening. However, when it sits like this, the flat portion of the gasket isn't touching the flat portion of the manifold flange - just the steel ring portion is touching, which doesn't seem to make a good seal. It doesn't make any sense to me. Seems the gasket shouldn't have this metal ring in it, and that way the gasket would sit flat against the manifold flange the way it should.
The old gaskets were in bad shape and mangled, so it was difficult to compare them with the new gaskets, however, I don't recall seeing any metal ring in them, and I know the flat portion of the donut gaskets were sitting flat against the manifold flange, with the manifold lip in the middle, because I had to pry them off the flange with a screwdriver.
I'm just wondering if the dealer gave me the wrong gaskets? I mean they fit fine except for that metal ring sticking out the flat side. The round portion fits perfectly inside the crossover pipe flanges. The only thing I could think of is if that round ring is supposed to be compressed down inside the gasket material as I torque down the flange bolts - I'm not sure its supposed to work that way though. I tightened the bolts down pretty good, but I didn't really crank them down.
I wish I had some pictures of what I'm talking about, but hopefully I described them well enough.
Anyone got any ideas?
I noticed when I got the gaskets, they both had this metal ring inside them, and sticking out about a 1/4" from the flat portion of the gasket where it should stick in the exhaust manifold flange. This metal ring looks exactly like a piece of exhaust pipe with the gasket material attached to it. I thought maybe this metal ring would fit inside the exhaust manifold opening, but it is too wide of a diameter, so it would only fit on the outside of the lip of the exhaust manifold opening. However, when it sits like this, the flat portion of the gasket isn't touching the flat portion of the manifold flange - just the steel ring portion is touching, which doesn't seem to make a good seal. It doesn't make any sense to me. Seems the gasket shouldn't have this metal ring in it, and that way the gasket would sit flat against the manifold flange the way it should.
The old gaskets were in bad shape and mangled, so it was difficult to compare them with the new gaskets, however, I don't recall seeing any metal ring in them, and I know the flat portion of the donut gaskets were sitting flat against the manifold flange, with the manifold lip in the middle, because I had to pry them off the flange with a screwdriver.
I'm just wondering if the dealer gave me the wrong gaskets? I mean they fit fine except for that metal ring sticking out the flat side. The round portion fits perfectly inside the crossover pipe flanges. The only thing I could think of is if that round ring is supposed to be compressed down inside the gasket material as I torque down the flange bolts - I'm not sure its supposed to work that way though. I tightened the bolts down pretty good, but I didn't really crank them down.
I wish I had some pictures of what I'm talking about, but hopefully I described them well enough.
Anyone got any ideas?