exhaust manifold, can it be fixed??

[cormac]

I have a exhaust manifold with a crack (large and rather severe in my opinion) from a '81 FI Spider, is there a way to fix this and have it be as good as the rest of the manifold? in reasonable condition? I would never think about passing along if I could not guarantee repair. FYI, the exterior crack corresponds to the inside crack and damage.

studs are fairly easy to fix

Thanks

[juvius]

you could grind the crack into a deep v and fill it with welds, then grind it smooth...

[cormac]

you could grind the crack into a deep v and fill it with welds, then grind it smooth...

but would it be as good or better than new?

thanks

[juvius]

it would be at least as good as the rest of the manifold...

[cormac]

it would be at least as good as the rest of the manifold...

hehehe, that is a better way to say it

thanks

[focodave]

Welding could be a little tricky, since it is a casting.
You'd have to heat the area up to cherry red with a torch, and weld while it's still very hot.
Tricky, but not impossible.
You'll either be successful -- or -- you will ruin the piece.
I would try it if I were you.

[cormac]

Welding could be a little tricky, since it is a casting.
You'd have to heat the area up to cherry red with a torch, and weld while it's still very hot.
Tricky, but not impossible.
You'll either be successful -- or -- you will ruin the piece.
I would try it if I were you.

thx

that pretty much settles it...wasn't going to use it for myself, but it sounds like fixing and selling wouldn't be ethical or advised so will junk

[81SPIDERMATT]

you should throw it up on free parts.... someone may see value in it ...i myself would try to fix it just for the experience alone of trying ..but probably would not pay to have it shipped .... hands on learning cheap "mechanic" that i am

[rebar1111]

Repairing cast iron can be satisfactorily performed.

One method is to insure the crack is "V" and drilled at both ends to prevent further crack propagation and then either braze or weld the "Ved" crack from drilled hole to drilled hole.

If welding use a Ni rod or high nickel alloy rod (stainless steel can work in a pinch).

A potential problem is that the carbon from inside the manifold may contaminate the braze/weld. But it is certainly worth a try.

[dmwhiteoak]

There are entry of manifolds out there to replace yours. I have one but saving it for a friend. Post In The parts wanted section.

[cormac]

thanks for the input...I was never planning on using the manifold as I am going to "custom" fab a header/exhaust, Columbia River Mandrel (long time provider of Fiat Spider header flange and header/exhaust parts) is a local company for me...

I was just thinking about fixing damage and selling...not in my plan anymore, feel free to PM me and I will be glad to give to anyone who wants to practice their "skills" on manifold...just figure the shipping from 97055

[So Cal Mark]

the real problem is that the metal is probably crystalized from excessive heat. You can figure that the metal around the cracked area is really weak. I'd certainly look into the cause, either fuel mix or timing or both are not right

[cormac]

Thanks Mark

the header came out of a car that was in storage over 25 years...engine being rebuilt from bottom to top to carbs

hey thanks for looking out for potential problems...appreciated