Cracked Exhaust Manifold

[Rich916]

Noticed some crakes in the manifold. I’m aware of different putty’s and fillers for fixing cracks but have no experience with them or even if they work.
Is this fixable or should I look for another Mani?

[68gmsee]

I'd look for another one. The location of the crack would be difficult to keep it sealed with any kind of epoxy. You have a lot of heat at that point and also vibration from the exhaust pipe. An epoxy would probably hold for a few days- maybe.

You could take it in to see if an experienced cast iron welder can weld it but I suspect the cost would be greater than a replacement. And, be aware that if you take it in for repair you may have to replace it anyway if the repair is not done right.

[mbgmike]

New one, throw that in the scrap bin

[GASoline71]

The Ram-horns are not hard to find... new and used. I would ditch that one.

Gary

[Rich916]

Originally Posted by mbgmike

New one, throw that in the scrap bin

Pretty much what I thought, I’ve seen different products for this type of repair. Just wanted a second opinion.

Thanks

[Bus Ted Knuckle]

I'd weld it. Why spend money on a new one when you can spend a few bucks on some nickle welding rods? If it doesn't work out, your not out much. Its worth a try for sure.

Drill the top end of the crack to keep it from spreading, V the crack out, preheat w/a torch and weld it.

[fastwillie 696969]

Originally Posted by mbgmike

New one, throw that in the scrap bin

i concur
cast iron welding is expensive and dangerous
scrap that exhaust

[Lee H]

Exhaust manifolds are cheap. Welding them never lasts long. I'm sure someone will chime in and say they welded one 29 years ago and it's still fine. Cut your losses and find a good used one.
Posted via Mobile Device

[MagmaJct]

I recently replaced my passenger side manifold because of a split up the center. Price from an eBay vendor wasn't too bad, around $45 if I remember correctly.

The only problem is it had ports for the AIR pump (which my truck doesn't have.) I had to find iron plugs from Home Depot to plug them. I used POR 15's exhaust grey paint and brushed it on.

Now the driver's side is leaking. Good time.

[mrein3]

Originally Posted by Bus Ted Knuckle

I'd weld it. Why spend money on a new one when you can spend a few bucks on some nickle welding rods? If it doesn't work out, your not out much. Its worth a try for sure.

Drill the top end of the crack to keep it from spreading, V the crack out, preheat w/a torch and weld it.

If your dead set on keeping an old cast iron manifold, my welding instructor outlined pretty much what Bust Ted Knuckle said.

***I've never tried this***

Heat up the piece with a torch. Weld the crack with high nickle rod. Bury the piece in sand so it cools down slowly or keep it warm and slowly bring the temp down using your torch.

Again I've never tried this or have ever seen it done. It is just what an old timer conveyed to me in a classroom setting.

Personally I'd find a good used one without the AIR ports in it.

[68 IRON]

Looks like it could be repaired...I think its worth a try. L6 manifolds arent everywhere any more. Repair and look for a replacement...someone here has one. Thats not a crack at the webbing is it? Might check for more cracks.