Welding Cast Iron Manifolds

**RPM016T** · 22-05-2009, 03:30 PM

Just wondering what experience people have had with doing this? Seen plenty of people do it, but wonder how long it lasts until they see cracking etc.

There looks to be some half decent cast iron 4A turbo manifolds on ebay.. just want to fit an external gate.

**The Real Roadrunner** · 22-05-2009, 05:40 PM

High nickel content rods are needed to weld it and it can be done but how long it lasts is completelr dependant on the parent metal, if its as porous as an aero bar don't expect it to last long.

cheers
linden

**Cuts** · 22-05-2009, 06:28 PM

if you do decide to weld to cast iron like TRR said use high nickel rods, and make sure you evenly preheat the job thouroughly (like hot, 350+ deg), then after welding put it back in the furnace and cool it down slowly, that'l give your best chance of it going well/lasting.

**actionDAN** · 22-05-2009, 08:11 PM

cast is really easy to weld. i welded steam tube to my evo 1 manifold for the wg port about 5 years ago with regular mild steel filler on about 100amps (dc) and its still exactly the same today. no cracks or anything. so many engineers hated the idea that i was gunna weld it myself and not take their advise and do it their way hahaha. just tig it man and be done with it!

**feral4mr2** · 22-05-2009, 10:17 PM

i found in the past brazing to be the best way to join cracks or other material to cast.

**cambelt** · 22-05-2009, 10:31 PM

Id be scared to weld a ebay cast product.
Dave

**Cuts** · 23-05-2009, 01:47 PM

Originally Posted by cambelt

Id be scared of a ebay cast product.
Dave

fixed

10 char

**aw11gte** · 23-05-2009, 04:54 PM

Depends on the steel content of what your welding. Ive welded a couple cast manifolds for turbos, one with an arc, just had to take it slow, and others with the mig, which is much easier. Even chopped and welded the stock skyline dump pipe to suit my needs and the manifolds and all have held up fine for a few years now with a turbo hanging off it and no extra bracing.

**jeffro ra28** · 24-05-2009, 10:30 AM

If you have a couple of days to do it and are using a stick welder, run one small bead and let it cool down totally before you run another. I have welded a few cast iron engine blocks this way and its about the only way it can be done without getting the block cherry red in a furnace before welding.

Like i said it takes a few days to repair a descent crack tho.