Exhaust Material to mate with Cast Iron

[mattnj]

The exhaust manifold is cast iron, I am going to fabricate a joining elbow for various reasons and adjust the water mixing position, what materials can I use to mate with cast iron (isolated with a gasket?) and to take the raw water and exhaust?

316 is the obvious choice, but it is a nightmare to machine and fabricate in general, is it the only option? :ambivalence:

 

[lw395]

You could use mild steel.
It should last a fair time.
If it works well, get a copy made in stainless.

 

[vyv_cox]

I see that quite a few marinised engines now come with aluminium manifolds, Beta for instance. I assume these are a 5xxx alloy, definitely would not use pure aluminium 1xxx. Galvanic activity with cast iron might be a problem but if all the wet part is downstream of the CI it should not be too bad.

 

[mattnj]

I see that quite a few marinised engines now come with aluminium manifolds, Beta for instance. I assume these are a 5xxx alloy, definitely would not use pure aluminium 1xxx. Galvanic activity with cast iron might be a problem but if all the wet part is downstream of the CI it should not be too bad.

my TIG welder isnt AC, so no can weld ali :-(

 

[vic008]

Made mine for the Bukh out of mild steel then galv. Lasted 10yrs

 

[mattnj]

Made mine for the Bukh out of mild steel then galv. Lasted 10yrs

Sounds like a plan! Thanks, wasn't sure if it was a big No No using mild steel with saltwater and hot exhaust...I shall give it a a go and keep an eye on it.