Is there any reason not to weld this up?

[sspeedstreet]

I had this crack welded up and the hole will need to be re-machined to accept a new freeze plug. I'm sure this was a spot for core support during casting; is there any reason not to just fill it in with weld instead?

[SappySE107]

RE: Is there any reason not to weld this up?

just fill it in and be done with it. As long as it doesn't leak you won't have any issues from it.

[firechiken]

Re: Is there any reason not to weld this up?

I had this crack welded up and the hole will need to be re-machined to accept a new freeze plug. I'm sure this was a spot for core support during casting; is there any reason not to just fill it in with weld instead?

Thats what all freeze plug holes are for.

[Lyle's GTP]

RE: Re: Is there any reason not to weld this up?

I would say that's too much welding on that manifold. That will put a very large amount of heat to it and it may crack in another spot, or distort the whole manifold in someway. Igf you are good with a burr and a flap wheel you can avoid remachining. I've done it lots before, just install the plug with some RTV silicone, and that will fill any minor gaps you have.

Lyle

[Streetrodder83]

If you have access to a welder and know how to weld aluminum or you know someone who does go ahead and weld it up. You shouldn't have any problems with heat distortion, just go slow with it. I should also mention that the TIG process would be the best way to go in this situation, due to the fact that it's cast and has a fair amount of impurities.

[RednBlack]

I saw this thread last night at work, and wasn't able to respond. I weld aluminum, MIG and TIG. Proper way to do it is, cut an aluminum plug that fits, the same thickness as the base metal. Chamfer the outside of the plug, and the inside of the hole. Gives maximum penetration and more asthetic look, and leaves a smoother transition on the inside of the plenum. It should be TIG'ed, as was mentioned, because of the impurities in cast, and it should be done in stages, about 1/2 " at a time, and allowed to cool. DO NOT PREHEAT! For the same reason you don't take aluminum parts apart hot! I am working on my own plenum, with a lot more welding than what you are needing, core plug included. FYI, Freeze Plugs are a misnomer, especially here, since there is no water behind that plug. But in a block, if it freezes hard enough to push these critters out, you have cracks somewhere. Most likely the heads, or thinner walls in the block. ....CORE PLUGS!!! Whoever came up with Freeze Plugs should be ...

[bud36light]

Again. JB Weld? Heh? Anybody?

[RednBlack]

Again. JB Weld? Heh? Anybody?

If you don't weld, or have access to someone that does, that works too. :P

[sspeedstreet]

When I said "fill", I didn't mean with weld material, I meant a welded plug. That particular spot in the casting is 7/16" thick. I think I have a piece of 1/2" plate at home. Should do fine.

Thanks for the input.