Strychnine

I've heard about people using it on their exhaust and headers before so I thought I'd try it because 3 of the runners have cracks around the welds. I let it sit until it was rock solid. I drove my car for about 10 minutes and started smelling the JB weld burning off, so I checked it out and it turned soft again. Did I do something wrong or are the cracks just too close to the engine where most of the heat is? The bottle said it could stand up to like 500 degrees. I'm not sure how hot a header gets....





This is before I put the JB weld on

SortaFlush

Just get somebody to run a line of new welds around it, even if it doesn't look as pretty, jb weld cant look much prettier...

Strychnine

I just needed a temparaily fix until tuesday when I can get my new header on. I guess I just won't drive my car until then so I won't risk burning valves.

Fabrik8

Your exhaust gets over 1000 degrees. JB Weld should never be used on a car, it's a poor solution for whatever you're thinking about using it on.

LD-rhdEG6

Agreed

jamminj6693

I agree with the two post above. Have it TIG Welded. I have had the same problem with my APS Headers,but once i rewelded them problem fixed.
JB Weld is not for this type of repair,and as Fabrik8 stated it never really should be used for automotive repair. So i would find some one who can TIG weld it and be done with it.

Fabrik8

By the way, is that a mild steel flange and stainless tubing? That doesn't work so well..

Strychnine

It's a knockoff header so it wouldn't surprise me.

Fabrik8

That would explain why it cracked, nickel alloys don't weld together with non-nickel alloys very well and their coeff of thermal expansions are different which means HUGE forces at the weld.

RCR Roscoe

i dont expect the jb weld will hold up, however id like to see what happens to the stuff if you try Do It!