Welding exhaust manifold

[kayarubin]

Hey fellow t4g'ers. Just seeing if it is possible to weld an exhaust manifold that is slightly cracked, or if it is better to just get one that isn't. And if yes to the latter, does anyone have a spare? Lol. Mine's suited to the big 16g. Bigger hole and ports compared to the stock vr4 galant with the 14b. Any help will be much appreciated! Kaya.

 

[BMGTZ]

Ive had manifolds welded on two seperate occasions .....one worked the other got worse within a week and was a waste of time!!

I have an evo 1 manilfold .....if thats any good to you?

 

[JayRome]

you can weld Cast, but you need to find someone that knows how to do it well.....

or just a new one...

 

[mannynz]

Yes you can weld on cast manifold, using proper welding rods.

 

[THE411]

And proper heat control!!!!!! preheat /arc energy/cooling rate are all crucial when welding cast

 

[Muzz66]

yes you can weld cast iron properly but one of the better methods is prohibitive cost wise and exceeds the cost of a new mani.i have welded a mani with an oxy and a special alloy (hence the cost, the alloy is a very fine powder and melts in the oxy sort of like spray painting molten metal and for the life of me cant remember what its called)and is sprayed on through the oxy when the mani is heated to the right temp very slowly. it is then buried in lime to cool down over a couple of days to prevent fractures.This method is ideal for building up rare vintage crankshafts and cams that cant be replaced.its been 15 yrs since i have done this so there may well be better ways now as I no longer work in that industry nor kept up with newer methods.

 

[omad]

If it's a stock galant one - don't bother. It's just going to crack again anyway. Renound for it. Get an evo one on there!

 

[kayarubin]

The evo mani's are cast alloy aren't they? Different metals used to the Vr's. I'm interested in the evo 1 mani BMGTZ as long as It's crack free and has flat mating surfaces! pm me if you you like to sell! Cheers. Kaya.

 

[BMGTZ]

I will have a look later tonight and get back to you

 

[kayarubin]

Thanks man! Get back to us about it when you can dude! Cheers! Kaya.

 

[mattrat]

can stainless be welded, mines cracking on one runner?

 

[Muzz66]

can stainless be welded, mines cracking on one runner?

Yes

 

[mattrat]

do i need to take mani off... cant i just run it so its hot and get some dude to weld it on the car?

 

[JayRome]

do i need to take mani off... cant i just run it so its hot and get some dude to weld it on the car?

if you want to kill all the electronics on your car..... go nuts.... lol...

 

[milkandoj]

Ive wondered about welding while parts are on the car, if you have the earth clamp next to where your welding not just on the body, and disconnect the battery would you be ok.

Or still no good dont do it?

 

[ENGINR]

Don't do it. For the extra bit of stuffing around getting the manifold off it's not worth the risk of destroying your ECU, wiring harnesses and fuses.

Electricity doesn't recognise how far/close the earth clamp is - it'll take the path of least resistance to earth and that will come down to the material.

 

[JayRome]

Ive wondered about welding while parts are on the car, if you have the earth clamp next to where your welding not just on the body, and disconnect the battery would you be ok.

Or still no good dont do it?

if your welding on you car, i'd suggest taking bat terminals off and unplugging your ECU (and anything else that you think may be disturbed ie: Carputers, decks etc) then covering wiring and anything you think might melt with cardboard or steel plates...

i'v welded on many cars, just taking those 2 major things off and i have never had a problem...

 

[Muzz66]

taking the mani off is sounding like a lot less work,lower risk and a better weld job to me. :thumbsup:

 

[milkandoj]

oh yeah for sure to take the exh manifold off is pretty quick.
I was more interested in what the experienced welders thought about welding on the car in general.
I was going to modify my exhaust slightly and i asked an exhaust shop, they said they weld on the cars all the time but i was still pretty cautious and did the job a different way.

 

[Dean]

Matty your a lazy bastard haha