Anybody try JB weld to fix cracked header?

[Blazer406]

I know it sounds crazy..... but with all the threads I read tonight concerning the infamous cracking problem with stock headers, has anyone tried JB Weld... or something like it to fix cracked headers?

Some of the posts suggest the headers usually crack where they were repair welded (in an area of the weld called the heat effected zone). Some suggest a gusset installed right where the DS commonly cracks (between #3 and #5).

I thought JB Weld might provide the adhesion to the header to seal the crack off without heating up the pipe around where you would normally repair weld it ..... therefore eliminating this "heat effected zone".

Any thoughts?

P.S. My boss and another colleague at work are degreed welding engineers. I will pick their brains tomorrow on this subject.

 

[disco stu]

Would never stand up to the heat. Have your co workers weld it with a triangle gusset between the pipes.

 

[Blown&Injected]

The only thing that type of stuff does is provide MORE CONTAMINATION for the welder to deal with at a slightly later time.

That plan is like a cow that does not give milk - udder failure!

 

[Ormand]

the heat effected zone

Is actually the heat "affected" zone, and is not part of the weld. The heat affected zone is the portion of the base metal adjacent to the weld, where the heat of welding can change the microstructure of the metal. In this case, the base metal is a 400 series stainless steel, which is not normally damaged by the heat. (Some 400 series alloys are hardenable, but not the one used for the headers.) But if it is welded using the wrong filler, or without proper use of a purge gas, then it may crack again, starting where the old crack was. Or it may crack adjacent to the weld, if nothing was done to reduce the thermal stresses, since the stresses were high enough to cause a crack in the first place, and now weld metal, stronger than the original, is in the place where the crack was.
Anyway, get it welded. JB Weld decomposes far below the temps that the headers will see.

 

[Blown&Injected]

TurboEnglish.com

I always hated that one. From some dictionary site (nice cite huh):

affect or effect?
Do not confuse the verb affect with the noun effect, which means the result of a particular influence.
Global warming is one of the most serious effects of pollution.
Do not confuse the verb affect with the verb effect, which is formal and means to make something happen.
The management wish to effect a change in company procedure.

And just to mix it up, psychology has yet another definition

 

[84gnguy]

I don't think any kind of epoxy or cold weld stuff will work on exhaust manifolds.Once it heats up and the crack expands,it'll just fall out,plus it smells pretty nasty too

 

[Jerryl]

.......Anyway, get it welded. JB Weld decomposes far below the temps that the headers will see.

As stated. JB weld is rated resistant to 500F.

 

[Blazer406]

I always hated that one. From some dictionary site (nice cite huh):

affect or effect?
Do not confuse the verb affect with the noun effect, which means the result of a particular influence.
Global warming is one of the most serious effects of pollution.
Do not confuse the verb affect with the verb effect, which is formal and means to make something happen.
The management wish to effect a change in company procedure.

And just to mix it up, psychology has yet another definition

I actually had it correct the first time... but when I previewed the post..... I elected to change it.... cause I thought it was wrong..... oh well..... I guess I had a 50% chance of getting it correct.

 

[OneLethal87GN]

What 84gnguy said is correct. I used it on my 85 GN's cracked header and it lasted long enough to get hot. I did it several times with the same results. Each time it got up to operating temps the stuff had already fallen off. Couple the high temps with a few WOT blasts and that crap won't last a few minutes on the header. I ended up just buying some K-B headers. I had the ones on my 87 welded by the guy rebuilding the engine and they're holding up fine.

 

[norbs]

Send them to me i can fix them fairly cheap

 

[yullose]

As easy as it is to drop a header off, why not just fix it right the first time ?
I did one for a buddy of mine and the whole job didn't take more than 2 hours start to finish. That includes cutting a triangle gusset from a piece of steel, and welding the header all back together...It was cracked almost all the way around.

 

[Blazer406]

As easy as it is to drop a header off, why not just fix it right the first time ?
I did one for a buddy of mine and the whole job didn't take more than 2 hours start to finish. That includes cutting a triangle gusset from a piece of steel, and welding the header all back together...It was cracked almost all the way around.

Did you use mild steel for the gusset? What kind of filler rod did you use? Pure argon for the shield gas? Tig or mig? I have everything I need here at work, but the filler rod. I will still have to get one of those. I weld with a MIG almost daily here at work and I have tig welded some in the past. Steel is not to hard to tig. Aluminum.... however is a challenge..... I would think stainless wouldn't be to bad as well... with the right filler rod... and shield gas. Also, did you back purge the inside of the header with your shield gas?

 

[yullose]

Did you use mild steel for the gusset? What kind of filler rod did you use? Pure argon for the shield gas? Tig or mig? I have everything I need here at work, but the filler rod. I will still have to get one of those. I weld with a MIG almost daily here at work and I have tig welded some in the past. Steel is not to hard to tig. Aluminum.... however is a challenge..... I would think stainless wouldn't be to bad as well... with the right filler rod... and shield gas. Also, did you back purge the inside of the header with your shield gas?

I didn't get too fancy with it...
Stainless wire and straight Argon would have been ideal if I had it here at the house. All I had was ER70 wire and Argon/CO2 mix. The gusset was just a piece of 3/16" mild steel plate. The weld flowed real nice and looked almost like it was tig'd. (I know how to weld)

 

[Blazer406]

I didn't get too fancy with it...
Stainless wire and straight Argon would have been ideal if I had it here at the house. All I had was ER70 wire and Argon/CO2 mix. The gusset was just a piece of 3/16" mild steel plate. The weld flowed real nice and looked almost like it was tig'd. (I know how to weld)

That sounds great. How long has your repaired header been in service?