Exhaust Manifold Repair Ideas

[Michael A.]

Attached is a picture of the drivers side exhaust manifold flange on my 66 327 with AIR. It has the original exhaust manifolds. As you can see the flange is broken by the stud. I am investigating options as to whether or not this can be repaired. I do drive the car and am planning a 5000 mile trip to the west coast and back this summer.

A local repair shop has suggested that welding and tapping a new hole for the stud would not work because the weld would be too hard and could not be tapped. They could weld a stud to the manifold and I could bolt the exhaust pipe to it... not very original but I would still have the original manifold.

Has anyone had experience with welding and tapping in this location? Any other suggestions or do I have a piece of original scrap iron with this exhaust manifold?

Thanks for the advice.

[Bernard M.]

Re: Exhaust Manifold Repair Ideas

Michael,

The exhaust manifold on the right side of my car has been welded and tapped at the inside stud position. It can be done. The only problem I have is that it is ever so slightly angled and makes it difficult attach the mating flange. If you attempt it, be as careful as possible in that regard.

Bernie Myers

[Mike M.]

Re: Exhaust Manifold Repair Ideas

our local machine shop has furnace- heated then cast welded worse looking cast iron than your manifold and they are still holding up on a couple of our sbc's. seek other welding facilities before you scrap the manifold. mike

[Patrick H.]

Re: Exhaust Manifold Repair Ideas

I purchased a manifold for my 71 that had a piece just like that missing. The local machine shop sent it out, and had it "spray welded" (their term). We ground it down so nicely and artfully that you can't tell it was ever broken. And, enough of the original hole was present that it was easily drilled and tapped.

It's fixable.

Patrick

[Michael A.]

Re: Exhaust Manifold Repair Ideas

Mike - thanks for the suggestion.

Does anyone in Illinois have a recommendation on a shop that does this type of welding. I am in Bloomington, IL but can travel for the right shop.

[Chuck R.]

Re: Exhaust Manifold Repair Ideas

Hi Mike,

Any reputable welding shop will be able to fill in the missing metal and easily drill and tap out the new steel. All they need to do is use a slightly softer rod. Making sure that the hole is tapped square can be tricky but it's not that difficult.

Pat was refering to flame spraying which is wild stuff but it's pricey.

Chuck

[Michael A.]

Re: Exhaust Manifold Repair Ideas

Chuck
Thanks for the info. I'm going to have to do some machine shop shopping here in Bloomington or Peoria to find someone who has experience doing this.

[Patrick H.]

Re: Exhaust Manifold Repair Ideas

Pat was refering to flame spraying which is wild stuff but it's pricey.

Chuck

I think mine was $30 or $35.
I wouldn't consider that pricey.

Patrick

[Chuck R.]

Re: Exhaust Manifold Repair Ideas

I wouldn't either Pat,

Man, time and technology have certainly aided this venue.

Back in the late seventies and early eighties when this process first appeared, a repair such as Mike's would have run in the range of $100 or better.

Guess they have come a long way baby.

Chuck

[Mike M.]

Try Jerry MacHeish

He repairs exhaust manifolds, and have them both reskinned at the same time so it won't rust.

http://www.z28camaro.com/index.html

[Michael A.]

Re: Exhaust Manifold Repair Ideas

Thanks everyone for the advice. It worked excellent. I found a shop in Peoria and when he explained that he uses a spray weld process that has been very successful I knew I was in the right place. I got a great recommendation from one of my co-workers who has used him for cylinder head welding and machine work so tonight's task is to remove the exhaust manifold and take it in for an estimate.

Thanks everyone for your input. I believe I'm on the right track now.

Cheers,

[Tom L.]

Re: Exhaust Manifold Repair Ideas

In the event that the shop in Peoria doesn't work out, keep Jerry McNeish in mind. He recently repaired a very similar problem on one of my manifolds. The repair looks so good, you can't tell he was there.

[Michael A.]

Re: Exhaust Manifold Repair Ideas

In the event that the shop in Peoria doesn't work out, keep Jerry McNeish in mind. He recently repaired a very similar problem on one of my manifolds. The repair looks so good, you can't tell he was there.

Thanks Tom. I'll keep him in mind. The big news is that the exhaust manifold is off! This is way too much fun!

Cheers,

[Michael A.]

Re: Exhaust Manifold Repair Ideas

Thanks to all who gave suggestions on the exhaust manifold repair. I just picked it up at the machine shop today. The did the spray weld technique and retapped the hole. They also shot blasted it and cleaned it up real well.

The weld is not quite as perfect as I would like but it is a vast improvement. You can tell it's been repaired. I'll take a picture and post it after it's installed.

A couple of questions for you all:

• Now that it's clean, should I "dress" it in some fashion or just leave it as is? I do drive the car regularly but some day intend to do a proper, body-off restoration.
• How should I clean the mating surface on the head? It is still installed on the engine in the car. Any good ideas on how to plug the exhaust openings in the head while still being able to clean the mating surface for the manifold?

Thanks,

[Chuck G.]

Re: Exhaust Manifold Repair Ideas

I've also seen broken ears repaired by welding a proper size nut within the broken area.

After the nut is attached, you "artfully" weld around it, using high nickel content or Ni Cad rod, made for welding cast iron.

Chuck