exhaust stud broke

[Redhillnm]

Had a similar problem with our '70. Right side of the V6 manifold flange that connects to the tailpipe was severely damaged. BOTH tabs broken completely off, PLUS a huge hole in the manifold just at where the front flange was supposed to be. Made a "gasket" like piece of mild steel (actually used two sheets of 1/16'), placed the broken pieces in their proper alignment, tacked with brazing rod, then TIG'ed around the perimeter of the manifold flange. Filled the hole with a chunk of 1/4 mild steel bar and TIG'ed that in place, too. Not very pretty, but certainly functional. Saved over $200 for a replacement.

 

[IOPort51]

soulds like the exhaust manifold was warped, Do you have the air injection manifold??

 

[Redhillnm]

No injection manifold. After I got the manifold repaired and went to install it, I discovered that, with the exhaust manifold studs at the flange having been inserted into the exhaust pipe flange holes, the whole thing was severely tweaked out toward the front. Finally just cut the exhaust pipe under the engine, installed the manifold and the chunk of pipe, and added a coupler to bridge the gap. Secured with muffler clamps. Works just fine. I guess the guy who tried to build the exhaust pipe parts was a bit short on the piece that connects the right bank to the main pipe going back on the left side.

 

[IOPort51]

the question was for Dalefan 88 about the injection manifold. I may have one some place off an 81 j-10 but it does not have air injection manifold holes.

 

[wrangler rider]

what i read of you breaking the manifold i would just weld it together, 1st its a jeep there made for patchy work and 2nd if you do it decently you shouldnt have any problems
and well you broke mise well try it, the worst that will happen is you put it on and it doesnt fit

 

[IOPort51]

I'm sure none of us would want to pass up an oportunity to do some "patchy work" but the exhaust on the AMC 258 i6 / 4.2l is kind of a pain to seal even when it is flat and pristeen. I think that has something to do with the intake being held by the same bolts.
It looks like exhaust manifolds are like cops, there is never one around when you need one.AMC 258 i6 / 4.2l exhaust manifolds are not , to my knowlage, an endangered species. Be cool, one will turn up. did you put a straight edge on the broken one to see if it was warped? or if you had something behind it?
In the best possible world you would put a 4.0 head on it and use the stock 4.0 header untill it cracked and then you could replace it with a real set of headers. Hours and hours or entertainment!!

 

[wrangler rider]

jb weld it!