How do you guys go about treating your Stainless manifolds after welding?
I have seen alot of pics where they have just been left as they are but doesnt Stainless rust if not passivated after welding?

 

STAIN less
less - no

no stain

 

Generally stainless will hold up just fine as is in the engine bay. It tends to turn pretty colors too.
-Michael-
Just an FYI, just because it is stainless, doesn't mean it is stainproof. Stainless can rust in certain situations.

 

stainless will rust if you polish it or prep it with a mild steel contaminated wire wheel. alos ive seen some 304 stainless rust as well.

 

Stainless will rust if it gets past a certain heating point.

 

If you don't clean the HAZ after welding (the rainbow colors) it can rust there.

 

304 doesn't seem to be the best at corrosion resistance, I personally use mild steel for manifolds and downpipes, and i just get everything ceramic coated after.

 

Sweet, so no need to worry for manifolds then?

 

It does take a while for ss manifold to rust, the owner usually got rid of the car/manifold by then.

 

Cheers guys,
Ive got a 304 mug I made about 6 months ago thats starting to develop some surface rust already

 

I use a stainless steel wire brush to brush all the stainless welding I do. Taking the "pretty colors" off of the welds seems to keep rust from forming.

Also stainless will rust anywhere you touch it with your fingers. I wear gloves on the final install of any parts.