Welding exhaust manifolds

[willowbilly3]

People who think they know say you can't. Only a few times that I can remember have I attempted and it always works. The last time was for a roundy round car and it made probably a dozen or more races before we got another, held fine. I did another one yesterday for my 300, the rear one for efi. I haven't ran it yet but it looks good so far.
I have a very simple method, no preheating or controlled cooldown either.

[binder56jd]

well???

tell the "very simple method"

bi
atch


did i say that??

[binder56jd]

cool beans man

that's the method i read on lincoln's site


http://www.lincolnelectric.com/knowledg ... reheat.asp


but, once again u give better detail

thanks

jd ho in training

[Fordlorn]

I am a welder by trade and yes, Willowbilly that is the proper method. The only thing I would add is that you should peen until you can put your bare hand/finger on the weld without burning yourself. It ain't pretty but when your combine or harrow bed is down and you need to get a crop outta the field, this will get it done. I'm right in the middle of farm country. You'll know if you did it wrong either right away or after a couple of thermal cycles when the weld (actually the area around the weld) develops cracks that run right along side of the weld/s.

[willowbilly3]

I am a welder by trade and yes, Willowbilly that is the proper method. The only thing I would add is that you should peen until you can put your bare hand/finger on the weld without burning yourself. It ain't pretty but when your combine or harrow bed is down and you need to get a crop outta the field, this will get it done. I'm right in the middle of farm country. You'll know if you did it wrong either right away or after a couple of thermal cycles when the weld (actually the area around the weld) develops cracks that run right along side of the weld/s.

I used to peen until I could touch it but I have speeded that up just a little. You can go a little faster after you are a ways in because the residual heat has spread to the rest of the part somewhat. I touch it but very quickly.

I have used a similar method only with the a slow cooldown to weld spring shanks on farm machinery. My welded ones outlasted some of the new ones, never broke one. That process is really slow and is only worthwhile if you have a dozen or so to do at a time.

[BobbyFord]

Don't know why anyone would go through that much hassle when you could go to the local pick-a-part and get an uncracked manifold for about $8.00...

[averagef250]

I do the same thing except use a needle scaler instead of a hammer. The needle scaler really peens the part and fast too.

I've found most gas stuff uses utter crap cast iron in manifolds and pretty much all around. Most of the diesel stuff I've worked on I've had no issue whatsoever using 70 series MIG wire to zip up a crack.

[averagef250]

The local pick-a-part will not have a DT466 manifold for $8.

I spent the last couple weeks searching for a 60's-70's passenger side 302 manifold with NO LUCK!

[willowbilly3]

Don't know why anyone would go through that much hassle when you could go to the local pick-a-part and get an uncracked manifold for about $8.00...

$20 and a 25 minute drive each way, which for some reason seems to kill a half a day. I normally wouldn't but I was at a standstill yesterday afternoon and looking at those cracked manifolds so i decided to give it a whirl. So an hour of my time and $5 in materials.
I wish I had a good needle scaler, not many shops seem to use those anymore.