Does anyone know if you can weld a leak/crack on an exhaust manifold?

Do i have to take it off the engine? Or can I take off the fuel rail, drain the lines/tank, and have at it?

 

You can weld it but more then likely it won't last very long. As far as welding it in place all depends on where the crack is and if you can get to it. Also if you do try to weld it in place other then getting any fuel away from where you are welding make sure the you disconnect the battery too.

 

High temp furnace cement works wonders

 

That depends. Is yours a cast iron or a tube style? I'm not sure what years had what.

Cast iron welding is for experts only. It's pretty tricky from what I've read. Not at all like welding steel.

Tube style is no problem for someone who knows welding, but still, like RTorrez said, it's not usually successful for long.

And think twice about using an electric welder on the vehicle. Even with the battery disconnected (an absolute must!), you can still produce eddy currents that can fry electronics.

Gas welding is no problem on the vehicle.

 

True! when I was working at an oil refinery we used some stuff called Kop-U-Coat. We used it on the tanks, incinerators and the cooling coils. I did use some of that stuff on my Chevy p/u manifold and it held for years. I also used it on my radiator when I had a piece of 2x4 go through it and it also lasted for a year until I changed it out.

 

Mine is cracked as well

 

Mine is cracked as well but weld didn't last a mouth

 

Unfortunately they usually don't last.

 

Yeah, and that's not specific to Cherokees. Exhaust manifolds in general just don't do well with welding.

I'm sure some folks have had success with it, but they are in the minority.

 

if its a tube style. good luck.. its probably cracked at the collector.. just find a good one at a junkyard if ya can.. maybe even find one thats stainless as there are a few aftermarket companies that make an improved stainless manifold, I don't know what the alloy is but you might be able to check with a magnet...

 

Stainless steel is only weakly magnetic.

 

Here's how I welded mine's. It's only been a few months, but it's still holding up thus far.
http://www.naxja.org/forum/showpost....3&postcount=21

 

I can see where adding the extra support may help it last a bit longer. But a little sloppy with the welds, Not much practice with your welder? Just messing with you. Keep us updated how long it holds out.

 

Mine is cracked right by the Falange part to hook doubt to the down stream pipe

 

Nope, I really didn't have much practice, I had to goto a friends house to use his welder which he hadn't used for a while either. Under time constraints and not been welding for many months, that was the best I could do. =/

As for the bracing, I was just copying what someone else on the forum there had done. He claimed his has been holding up for 7 years so far. We'll see what happens. So far it's holding, so I'm happy.