Help - exhaust manifold leak • The Dodge Challenger Message Board

by **Steve R (Rizrtse)** » 03 Nov 2002 0:59

Sounds like I have an exhaust manifold leak on my recently rebuilt 383 Magnum 70 RTSE. I have the original manifolds with stock gaskets, which were changed 1,000 miles ago. Should I mill the manifold? Are their better aftermarket gaskets? Is anyone making 70 383 manifolds in case I find a crack? Sounds like a good time to relace the manifold sleeves as well, since the stock ones were used and their was some weeping until we sealed it. Need advice.

by **Jens (Jj)** » 03 Nov 2002 14:40

Hi Steve,
check first if the leak is between the exhaust
manifold and the cylinder head. I had the same problem on my old corvette, now 12 years ago. There was a leak at one exh. manifold after 500 Kms driving. I bought some high-quality aftermarket gaskets from FelPro, put them in and the leak was gone.

Regards, Jens

by **Steve R (Rizrtse)** » 03 Nov 2002 15:20

So felpro is the best on the market for Mopars as well? Do you have their number?

by **Jens (Jj)** » 03 Nov 2002 17:52

Sorry Steve, I do not know, if they are the best on the market.

Check an internet search engine for "fel pro gaskets" . There you should get all the informations and numbers.

by **Dave_R (Roppa440)** » 03 Nov 2002 19:36

The soft copper or aluminium gaskets are the best. Designed for headers that always leak easy but I think they fit original manifolds too? Look at summitracing.com

by **Luke (Luke)** » 04 Nov 2002 12:08

to cheeck where the leak is coming from, use a lenth of hose (any hose will do i use a bit of fuel line 3/8 id) put one end to your ear and the other to where you think the leak is by moveing it around you will find it.

by **Dave_R (Roppa440)** » 04 Nov 2002 13:34

It would be funny if the hot exhaust gasses went up the tube wouldn't it? That would take care of those ugly ear hairs us older blokes get!

by **Donald Luke (Oerm2133)** » 12 Jan 2003 16:11

Quick question - are you sure the exhaust leak is from the exhaust manifold area? When engines are rebuilt, we generally get the heads reworked as well. If the heads are surfaced too much and the intake side of the head not compensated with a sufracing as well, the intake manifold may not seal right to the head. This could cause an exhaust leak at the exhaust passage going into the intake manifold. I chased an exhaust leak on a 383 only to find a cracked exhaust manifold - the crack was on the back side where I couldn't see it until I removed it.