Exhaust Manifold

[PeeJay]

Alu or Cast Iron?

I'm trying to convince my mechanic to weld it up for me. He says it could be a specialist job.

 

[crespo]

Its definitely not alloy.

 

[vile]

Alu or Cast Iron?

I'm trying to convince my mechanic to weld it up for me. He says it could be a specialist job.

Im not 100% but there was a member hear that had his welded.Im sure Dan had his done as well.Have a search in the google search as this will be there for sure.

 

[F6HAD]

Definitely not a specialist job, and cast iron.

 

[speedthing]

its cast iron and it tends to crack on the corner of the manifold at the timing chain end one of the mechanics i know at blade honda in cheltenham told me that they did manage to weld one up with out removing it.

 

[PeeJay]

Thanks all,

I managed to source an uncracked (but early) model one reasonably cheaply via eBay. I'm going to take it to a local welding place to be toughened up. If the old one is repairable I'll also ask them to weld that one up and I'll keep it for a spare or reBay it.

 

[H Peasource]

The OP's mechanic is sort of right. Welding cast iron is something for a professional welder to do. It's not too difficult but it does need special electrodes and a particular technique to make a good weld.

Alan

 

[Terry124]

Are we sure that its cast iron?

The photo's loaded previously re welding the manifold were completed by a MIG welder and I have not seem dissimilar or cast welding wire for MIG's?
Secondly my experience is that IF you try to weld cast iron using MIG/TIG/ARC it is VERY prone to cracking as the material is very brittle and does not appreciate localised temperature changes.
Welding cast iron is usually undertaken by heating the entire unit in an oven to red hot then removing it quickly, apply local oxy/acc torch and weld, once completed put casting back into furnace (switched off) and let it SLOWLY reduce in temperature.
Its why I guess cast iron is usually cast and machined but not welded.

I suspect that the manifold is some type of cast steel but have never touched one off a Honda, but you live and learn

 

[Frutibunn]

I welded mine 2 weeks ago and so far so good, i used a normal mig welder as the manifold appeared to be steel and had been welded during the original manufacturing process. hope this helps

 

[speedthing]

ive welded cast iron manifolds loads of times with no problems think i even welded up my last vectra manifold went on to do 50k in that never had a problem with it.

 

[H Peasource]

I must admit I'd ***umed it was S.G. cast iron, which is weldable. How easy it is to weld depends on the thickness of the casting - the thicker it is the more specialist the job becomes. Thinnish castings can be successfully welded using MIG/TIG or arc but arc is normally used because of the cost. The filler matrial used is an expensive nickel alloy - a few electrodes for an arc welder or a few filler rods for a TIG is one thing but a 5 kilo drum for a MIG welder is something else in cost terms.

Alan

 

[F6HAD]

Plenty have been welded now guys, no issues if done properly.