Exhaust manifold to pipe connection

[82BlazerMan]

I've been trying to get rid of a exhaust leak at the manifold to pipe connection and it seems like nothing I do seems to work.  I think the gasket I've been buying is the wrong one.  It looks like a donut and does'nt seem to fit right, although it will last for while, the leak always comes back.  Am I going to have to take it to a muffler shop and have new pipe flanges put on so it will seat up to the manifold right?  When I say seat up right, I mean I don't think it used a gasket originally and the pipe just seated to the manfold directly.  Hope this is not too confusing.  

[Lt.Del]

It just stuck there with no gasket.  It fit inside the manifold if i remember correctly.  

If it keeps messing up, and no holes are evident, that means there is too much stress at that point.  Sometimes a new hanger clamped around the pipe under your cab will relieve the stress and the joint will stay put.   Ensure you have lock washers on the threads that come out of the manifold along with the nuts.  

SgtDel
aka "Andy"

www.delbridge.net

1979 Big 10 383 stroker
1991 Blu 'Burb 3/4 ton 4x4

[123 pugsy]

I had a problem with the foil looking donut gaskets before.I got a solid metal one ...no more problems....

[82BlazerMan]

Thanks for the tips.  Now that I think about it, it seems the pipe fits too tight against the cross member.  That could be causing it to fail.  I think I'll try the metal ones too.  I'll post how it went this weekend.

[82BlazerMan]

I tried the metal donut and it would'nt work becouase the bolts ended up being too short.  I think I'm just going to have to take it to a muffler shop and have new pipe fittings made.   Hey, maybe I'll just buy some new headers instead.

[Blazin]

I have the same problem with 79 K30 dump. I have replaced everything, the studs, the donuts, the hangers, another set of manifolds with another set of studs, brass nuts, steel nuts, etc. yet they last for about 2 months and then leak again. I too am thinking of headers.

[Lt.Del]

This may be common sensical, but are you guys trying lock washers with your bolts for the flange??  Or is it still remaining tight but leaking around it??

SgtDel
aka "Andy"

www.delbridge.net

1979 Big 10 383 stroker
1991 Blu 'Burb 3/4 ton 4x4

[Blazin]

I have used lock washers and lock tight. That solved to losening problem no it just starts leaking after a month or three. Took it all apart again about two months ago redid everything etc. Two weeks later the gasket belw out between the head and the manifold. *@&^*%#)#**!!!! <p></p><i></i>

[joesgarage71]

 I installed a engine in my 78 and while rounding up parts,I found a set of exhaust manifolds with pipes attached I had stahsed in the shed,Taking them apart to replace the dounuts there where sleeves inside,That the dounuts slid over and I installed this sleeve inside the pipe and bolted the manifold and pipe together. Maybe something like this might help.I might have one I can take a pic of, I'll have to look.
 Steve

[Blazin]

Its time for a major overhall anyway. Got allot of little things to do this summer. the rear brakes just mysteriously stopped working. clutch linkage is worn out, etc. etc.