Welding cast manifold???
Thread Starter
TECH Senior Member
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From: GA, USA
Welding cast manifold??? Have read the various posts about this procedure, and understand the basics.
I have 2 welders.. A TIG, and a MIG.
I have mild steel wire & stainless wire for the mig.
I have mild, stainless, and silicone bronze for the tig.
The manifold in ? is a 6.0 truck manifold that I had to mill off on 1 side, for steer gear clearance. [2x4" hole]
The hole has been covered w/ 1/8" mild steel plate. The manifold can be pre/post heated. I have temp sticks to control the heating.
Suggestions as to which welder and wire would be most likely to produce the best results, are appreciated.
I have 2 welders.. A TIG, and a MIG.
I have mild steel wire & stainless wire for the mig.
I have mild, stainless, and silicone bronze for the tig.
The manifold in ? is a 6.0 truck manifold that I had to mill off on 1 side, for steer gear clearance. [2x4" hole]
The hole has been covered w/ 1/8" mild steel plate. The manifold can be pre/post heated. I have temp sticks to control the heating.
Suggestions as to which welder and wire would be most likely to produce the best results, are appreciated.
Joined: Aug 2007
Posts: 24,241
Likes: 89
From: Turnin' Wrenches Infractions: 005
I would like the tig for this application but either should work fine. However, if it is a shitty cast I think you will have trouble welding it decently. In the casting process, often times bubbles, or lots of them, are trapped inside the metal. Welding will release these. If its a good cast there may be little to no bubbles and welding will go quite smoothly, much like welding steel plate. If its a shitty casting, and there are lots of bubbles, good luck welding anything to it. It will literally bubble like the metal is boiling, usually ending up in one shitty weld. My .02.
Thread Starter
TECH Senior Member
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Joined: Jun 2004
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From: GA, USA
Thanks for the reply..
So far, I've tried the following:
All tig. Weld w/ mild steel, no preheat. Heard it "snap", see no cracks.
Then, preheated, same mild weld. No cooling "snap".
Then welded a scrap to a junk manifold. No preheat. Snap. No cracks seen. I broke the scrap piece off w/ a pliers. The weld let go on the scrap part. Manifold held.
Did the silicone bronze and scrap weld, preheated. Looks good, and the scrap is not budging!
I may just go w/ the silicone, pre/post heat/cool, and call it "nice"!
Getting a set of headers to fit w/ an LSX in a 55 is a PITA!
So far, I've tried the following:
All tig. Weld w/ mild steel, no preheat. Heard it "snap", see no cracks.
Then, preheated, same mild weld. No cooling "snap".
Then welded a scrap to a junk manifold. No preheat. Snap. No cracks seen. I broke the scrap piece off w/ a pliers. The weld let go on the scrap part. Manifold held.
Did the silicone bronze and scrap weld, preheated. Looks good, and the scrap is not budging!
I may just go w/ the silicone, pre/post heat/cool, and call it "nice"!
Getting a set of headers to fit w/ an LSX in a 55 is a PITA!
Thread Starter
TECH Senior Member
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From: GA, USA
Got'r done...
Preheated to 500* w/ a torch. Welded an inch, added heat.. repeated until I was at the point of tacking in the 2nd piece. Put it in a bucket, filled it w/ floor dry, let it sit for an hour. Temp was down to 80*. Welded in the last piece, repeated the cool down...NP. No popping, cracking. Off to the coaters!
Preheated to 500* w/ a torch. Welded an inch, added heat.. repeated until I was at the point of tacking in the 2nd piece. Put it in a bucket, filled it w/ floor dry, let it sit for an hour. Temp was down to 80*. Welded in the last piece, repeated the cool down...NP. No popping, cracking. Off to the coaters!
Excellent, this is what my friend did for me, preheated the manifold and kept it warm throughout the process and tigged them up, they came out beautifully 
Glad you got her figured out, post some pics when you get a chance
Glad you got her figured out, post some pics when you get a chance
Launching!
Joined: Sep 2009
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From: SOUTH CAROLINA
hi,
the aforementioed is correct.......arc welding,brazing or tig with proper prep work which is a must. use a reputable welder and the correct repair materials.
good luck have a blessed day........jim
the aforementioed is correct.......arc welding,brazing or tig with proper prep work which is a must. use a reputable welder and the correct repair materials.
good luck have a blessed day........jim
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The absolute best way to weld cast iron manifolds is to fusion weld (Cast to cast) them. Although, arc welding will work, it can be difficult to weld right and get good results. Before having them coated, i would HIGHLY recommend either magnetic particle checking them, or use some form of dye penetrant to make sure it didnt crack.
I work at a company that specializes in cast iron repair, and we never arc weld cast iron. Ive seen too many parts that were ruined, because it wasnt done right.
I work at a company that specializes in cast iron repair, and we never arc weld cast iron. Ive seen too many parts that were ruined, because it wasnt done right.
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TIG welders are freakin awesome, definitely versatile. 
brazing would have been easiest most likely...
Ive had to weld large 3foot diameter cast flanges to mild steel and I pre heated with several torches, and used some ni99 rod from my supplier with decent results. I dont like arc welding it though, too many worries...
Ive had to weld large 3foot diameter cast flanges to mild steel and I pre heated with several torches, and used some ni99 rod from my supplier with decent results. I dont like arc welding it though, too many worries...
well... i have no idea how mine held... i cut off the flanges and rewelded them just welded at large tack on 3 different sides and then welded the whole thing. no preheat, ran for 8 months with no cracks ended up selling the kit.
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Joined: Jul 2004
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If it's a good casting then weld it with whatever you're the most comfortable with. The fact is the more time you spend futzing with it the more likely you are to have problems.
With crappy castings the only way is to braze it
With crappy castings the only way is to braze it
The real question is, is the manifold you are talking about
really cast iron, or something else like nodular / ductile
iron.
If it drills out like powder then it's cast. If it makes curlies
it's ductile and you can get away with a lot more careless
work.
really cast iron, or something else like nodular / ductile
iron.
If it drills out like powder then it's cast. If it makes curlies
it's ductile and you can get away with a lot more careless
work.
yes, that is what they are doing.
If it drills out like powder then it's cast. If it makes curlies
it's ductile and you can get away with a lot more careless
work. i like this, never knew that.
If it drills out like powder then it's cast. If it makes curlies
it's ductile and you can get away with a lot more careless
work. i like this, never knew that.