Welding V Bands To Truck Manifolds?
03-08-2012, 12:23 PM
#101
FYI - The only reason you preheat something is when you are welding like a thin piece to a thick piece, the thin will cool faster than the thick. This was needed because of how brittle cast iron is. Thin cast iron does not really need to be preheated. You dont need to preheat these manifolds.....waste of time. After welding 1 inch on them they are plenty preheated and the manifold is thin enough where the flange isnt going to cool faster than the manifold.
03-08-2012, 12:37 PM
#102
FYI - The only reason you preheat something is when you are welding like a thin piece to a thick piece, the thin will cool faster than the thick. This was needed because of how brittle cast iron is. Thin cast iron does not really need to be preheated. You dont need to preheat these manifolds.....waste of time. After welding 1 inch on them they are plenty preheated and the manifold is thin enough where the flange isnt going to cool faster than the manifold.
03-08-2012, 02:34 PM
#105
If Im using mild steel, I usually just get mandrel bends from Jegs/Summit. If Im using stainless, I use Ace stainless or Columbia River.
06-01-2012, 01:01 PM
#109
Bringing this back from the dead. What have you all found more success with; welding mild steel v-bands to the truck manifolds, or stainless steel? If mild steel v-bands - what filler rod? I think the consensus was 309 for stainless.
Which one out of the two would be less prone to cracking?
Which one out of the two would be less prone to cracking?
i gotta do some. 
12-13-2012, 09:41 AM
#112
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Yep, I am resurrecting this thread. I am interested in finding out what these new "cast iron" manifolds are made of. I have fixed cracks in old, old CI manifolds and they could not be welded. I had to preheat with a torch slowly and I braised the crack. Of course a braise will seal a crack but is not good for a load bearing joint. I have tried to weld on "true" cast iron and it cracked. My guess is it is too much heat focused into a very small area. I saw an old timer, welder extraordinaire, master welder weld CI and he drilled holes before welding along the weld for expansion purposes and then welded the holes up. I am not sure how he did it, but if I keep welding for 50 more years maybe I will figure it out.
Someone said you have to preheat when welding a thin piece to a thick piece. I think you have to preheat when you are welding two different types of material because they have different expansion rates. Two different thicknesses of the same material will expand closer together than two dissimilar materials such as ms/ss and cast iron.
Someone said you have to preheat when welding a thin piece to a thick piece. I think you have to preheat when you are welding two different types of material because they have different expansion rates. Two different thicknesses of the same material will expand closer together than two dissimilar materials such as ms/ss and cast iron.
01-14-2013, 03:32 PM
#113
these appear to be some sort of cast steel... they tend to be really easy to weld. Old school "cast iron" manifolds can be hit or miss. I had a set that I ended up cutting apart and rewelding to work in a chassis that the engine was never intended for, and it was a piece of cake... till I got to a small, hairline crack in the face of the manifold, nowhere near any of the other welds. That one as soon as I hit with an arc it was like the metal would vaporize in front of me and I'd be chasing a hole or a crack the whole time. I suspect that there was just some junk in the casting in that spot. I tried grinding the crack out and welding it, i tried all sorts of different technique... nothing worked. I finally gave up and just brazed it and called it a day.
04-22-2013, 03:37 AM
#114
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I got a set of 01 5.3 manifolds, that have the egr on the passenger side. Got them for free, and gonna try using 309L arc welding rod. Not sure why you would use NI99 when you can get 309L Rod for like 10.00 a pound. Should only need two to three rods, and got like 13 rods for 10.00. Welds easier than 7018, but is faster. Puts down a perfect weld too. Gonna try heating the manifolds first, and then tacking the vband in 4 spots, and then trying to run two or one bead all the way around. Not sure if I will have to stop or not. Have a scratch start tig setup, but not sure if I want to try it, since I only have a 17v torch. I'll post a picture when I'm done. Do you guys ever try to weld the egr shut, or just avoid the egr manifolds. In the first pictures, it shows a set with the egr.
Here is a vband I stick welded to a piece of mild steel 16ga exhaust pipe. A source for the rods too.
http://airgas.com/browse/productDeta...ct=RAD64001167
[/QUOTE]
Here is a vband I stick welded to a piece of mild steel 16ga exhaust pipe. A source for the rods too.
http://airgas.com/browse/productDeta...ct=RAD64001167
[/QUOTE] Last edited by jvan; 04-23-2013 at 02:02 AM.
07-31-2015, 11:02 AM
#115
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well fellas i think there are a few different kinds on manifolds out there. i welded some on my car a long time ago and they welded slick as glass with my TIG, built a turbo kit for a friend this past week and did the same to his the same way as i did mine.... absolute junk. cracked the entire weld on one side. tried with er70s, 316ss and 308. didnt have any 309 so i gave up and scrapped it to a use a new manifold. i feel like these things are hit or miss
11-10-2015, 03:04 PM
#117
This thread was great when I did mine last year. About to do another set and re-reading it I'm wondering If I should use the 309 MIG wire this time instead of standard MIG wire?
12-21-2015, 06:46 AM
#119
Bringing this back up. I tried welding up a set of 01 5.3 manifolds yesterday and it was crack crazy. I was using 160 amps 3/32 tungsten and ER70 filler. After all the cracking, I switched to 308 filler and that was a lot better, but still I ended up chasing cracks all over. Maybe I didn't pre-heat enough, but I used a MAP gas torch for about 5 minutes before welding, no post heat because the cracks would all show up before I was even done welding. The 2 pieces I was welding together were both the same material (I just cut and re positioned the manifold outlet). Both pieces were freshly grit blasted to a bare clean surface so there was no contamination likely. What gives? Could there be casting material differences in these manifolds?
12-21-2015, 08:45 AM
#120
Bringing this back up. I tried welding up a set of 01 5.3 manifolds yesterday and it was crack crazy. I was using 160 amps 3/32 tungsten and ER70 filler. After all the cracking, I switched to 308 filler and that was a lot better, but still I ended up chasing cracks all over. Maybe I didn't pre-heat enough, but I used a MAP gas torch for about 5 minutes before welding, no post heat because the cracks would all show up before I was even done welding. The 2 pieces I was welding together were both the same material (I just cut and re positioned the manifold outlet). Both pieces were freshly grit blasted to a bare clean surface so there was no contamination likely. What gives? Could there be casting material differences in these manifolds?
Did you prep them beyond the blasting? Even when I weld a blasted set I still flap wheel or roloc down to nice shiny material.
I purge and weld these up around 130 amps and run a realllllly slow puddle.
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