Crack in manifold

[Axell]

Hi.

Today I noticed a crack in the manifold of my super major. Some soot has blown out around it.
I don't have any experience in welding and also read it is difficult and risky to weld cast iron.
A new manifold isn't cheap.
Anything I can do to prevent the crack from spreading?
A large hose clamp?

 

[Majorman]

I would not weld it, just clean it, groove it if possible and use something like JB weld. You could
also, if possible, drill a small hole at the ends of the crack to stop it running.

 

[Axell]

Yes could try if jb weld can withstand the heat.

 

[DanielW]

If it were me I'd unbolt the pipe/U (probably have to cut the bolts off) V it out and braze the crack with the manifold in-place. If you don't have brazing torches, however, you'd have to get someone to come there to do that, and it'd probably be easier
just to unbolt the manifold and take it to them. Shouldn't cost you much - any welding shop should be able to do that for $50 or so. You'd need new gaskets, unfortunately, but they're readily available anywhere (Sparex sells them, and pretty much every
dealer can order from Sparex).

 

[Fritz Maurer]

Take it off and find someone to fix it. This is not a difficult
repair. It will be harder to fix after you let it break all the
way off. Gobbing epoxy on it will accomplish nothing.
What can you do to keep the crack from spreading? With
all that weight overhead, you cant even slow it down.

 

[560Dennis]

Definitely drill a small hole 1/8 to 3/16 at end of crack as suggested. This will stop it from spreading further . Do this first.
Then to get the flange bolts out from what I see . Preheat the area first , If you used a torch then to heat the nuts ( incandescent color) up
and ,take bolt out from cracked side first remove them .
Then take manifold off engine.
Id use a du-more grinder to V out crack and fill nickel rod ,or braze . You must preheat the wide area to weld it (also braze) to about above
450 F .
Or take to someone .
What I suggest from the one picture .
Good luck and lets hear about the fix.
T

 

[Axell]

After a little better look it seems like the crack goes all the way to the edges. So no drilling needed. Doubt I can get these bolt and nuts off. The whole exhaust and elbow looks very rusty. So perhaps a new set is in order. Just hope the manifold isn't too stuck and the doesn't studs break.

Thanks for your advices.

Btw, is the exhaust pipe supposed the sit loose in the elbow and wobble when driving?

 

[DanielW]

I doubt the pipe is 'supposed' to be loose, but a lot of Majors I've seen with the vertical stacks have the pipe/muffler loose so you can lift it off to open the hood. The earliest Majors had underslung exhausts and thus it wasn't an issue.

I've definitely seen worse manifolds. Cut the bolts off, use some heat to get the nuts off the studs, and it'll braze up pretty easily.

 

[Majorman]

Yes, the pipe is a loose fit in the manifold elbow and has been from new.