Welding on stock exhaust manifolds

[Broncoholics]

Anyone ever weld on their stock exhaust manifolds if they crack?

One of mine has a hair line crack and does not leak yet but looks like it could break in half. The crack is in the middle going from top to bottom.

I doubt it will break in half since its bolted up but if it leaks I will have problems.

Since its cast iron I was thinking of getting the engine up to temp so it its easier welding. Will this cause future cracking problems where I weld? Or blow holes in the mainifold and cause more problems? I'm going wheeling this weekend far away and don't want to see it fail. Let me know...

 

[Bully Bob]

Hay Mr. Holics,

FWTW, my 305 right exh. man. cracked & "ticked" for quite a while. Couldn't see much as the heat shield (amother things) hid it.

When I took it out , it was in "3" pieces....! Quick run to the boneyard & I was good to go.

My guess is the "heat-riser" stuck & over heated that side.

Doubt welding is anything more than a waste of time.

B

 

[Broncoholics]

Some say to use nothing buy nickle rod. I found a guy that will give his up for the freight cost. Works for me. The pass side always ticked. I had the manifold resurfaced and the tick is gone! *******, its never been this quiet! I'll probably play around with it when I get another replacement since I love welding. It needs to be welded in place due to warpage and it need to be up to heat (running motor) in order to get good penetaration. Sounds reasonable...

 

[stubby]

i've welded more than a few manifolds- not cast though- i knew a guy who used JB weld as a cheap fix once... if you try to weld it make sure you clean the crack really good- and have patience