[micifus]

I need to patch a hole in my exhaust will JB weld hold up to the heat? I know someone here patched there cracked header how did it hold up?

[greasefingers]

Go for it man!

JB weld is amazing stuff. I would try it and see how it holds. I have no experience with it and heat. The outside of the muffler is not as hot as one would think. The exhaust manifold inside gas temp is freckin hot!

[ArloGuthroJeep]

People using it on their exhaust manifold say it only holds for a week or so...

[Zlartibartfast]

If you want it really fixed, it'll need to be properly welded. That means removing it from the block. If you're going to that much effort, get a proper header to replace it.

You can use JBweld as a temporary patch; just clean the metal surface thoroughly, and plan on repeated applications

[greasefingers]

Where exactly is the hole? Header, pipe, or muffler?

[brsox88]

I would buy an exhaust clamp sleeve. Then buy some exhaust putty or glueish type stuff. Lay that inside the sleeve and put the sleeve over the whole. Best cheap way to fix a hole in an exhaust.

[Country Boy]

JB will work on the rear parts of the exhaust system, but not near the manifold. I put some on my manifold and it lasted all of 3 minutes. I found a product called Thermosteel that seems to be working. I put it on two weeks ago and its just as hard now as then. You put it on and let it cure for 3-4 hours, then slowly heat it to fully cure it. I got mine at Advance Auto Parts. The product claims to be able to withstand 2400* F. It was about $6 for a small jar.

[melonman]

Hey Silver Stihl,
Let us know in like a month if it is still holding up. Where is your patch located? I have tried as couple things on the infamous exh. header collector crack / leak on my '96 I6 and they might last like a month but it is so hot right there-I didn't really expect to hold and it is so hard to get the patching compund / wrap etc. in and around where the leakage is (multiple pipes come together) so getting a good patch is next to impossible to begin with. I might want to try that thermosteel stuf but wanted to see if you were using it in an intense type location or not.

Thanks,
Larry

[Country Boy]

Mine is right where the last two pipes come together before the down pipe attaches to the header. I just used my finger to scoop it out of the jar and worked it into the cracks. I ended up putting it all the way around both pipes instead of just the cracked one. I'll keep you updated on it, but using that product and replacing my O2 sensors took care of all the problems I was having with my ZJ. It drives like a dream now. I have a feeling the O2 sensors were bad because of the excess fuel being dumped into the system causing excessive buildup of soot on the sensors.