Crack in Intake Manifold

[DD16]

I was using Evaporust to remove accumulated rust in the interior of the manifold. I noticed a leak in the tube just above the flange that attaches to the cylinder head. Further inspection revealed a crack of about 40 degrees of the circumference clearly visible in the interior. Is such a crack repaired by brazing? Would the heat generated by brazing be enough to warp the assembly? If not brazing what method of repair is used, if any?
Thanks

[Hardingfv32]

Brazing is appropriate. Will not have an issue with warpage.

Put most the heat (all of the flame) into the flange. WAIT till the rod melts onto the flange. The tubing is only .030-.050 thick. Start clean and use lots of flux.

Brian

[DD16]

Thanks Brian - appreciate it.

[problemchild]

I was using Evaporust to remove accumulated rust in the interior of the manifold. I noticed a leak in the tube just above the flange that attaches to the cylinder head. Further inspection revealed a crack of about 40 degrees of the circumference clearly visible in the interior. Is such a crack repaired by brazing? Would the heat generated by brazing be enough to warp the assembly? If not brazing what method of repair is used, if any?
Thanks

While Harding is correct in his assessment, the number of people these days who are comfortable with a brazing torch, is few. I am, and I would be very intimidated by this job. I would certainly prefer to have one to practice on. Rather than end up with complete junk, unless you have someone who you have complete confidence in, I would go the epoxy route. I would do it with the manifold bolted down on the engine and I would do several applications, very minimal, applying above the crack and running down over it. Might not be very pretty, but as legal a repair as there is, and in my opinion, more durable, and less risky. You may even want to go the epoxy route until you find someone you trust to take the torch to your manifold.

[Earley Motorsports]

Got a picture of it?

[Hardingfv32]

...the number of people these days who are comfortable with a brazing torch, is few.

"A man's got to know his limitations"

Epoxy is fine, but will not stop the crack from spreading.

ALL manifold installations should incorporate a brace to the case. The manifold should never see any loads from the throttle cable system.

Brian

[DD16]

No pics as manifold already at FV prep shop who has done this before. Shipped it as soon as Brian replied and I checked with the shop. Brian, any pic or diagram on brace?

Thanks all for your feedback. It is very helpful.