De-rusting cast iron turbo manifold

[Raf99]

(I was not sure where to post this, please move it if needed).

I've been searching for over an hour without much luck. I found one post by cpmike about de-rusting a manifold but his youtube links did not work (original owner removed account) and he also stated later that the process failed (paint bubbled off). I could not find any other posts on cb7tuner regarding this topic. I found other mustang forums that mention taking a sand-blaster to manifolds and having it professionally cleaned (sand-blasted, primed, baked, painted, baked, x2).

I was wondering if anyone has any ideas on how to clean the below unit? It's cast iron, very heavy, very thick and its just surface rust. I read about using sand paper, or a bristle brush, and other methods and I wanted some opinions. Obviously the area that meets the head will need to be sanded and painted to have a proper seal too. Does anyone have any ideas that I can personally do here @ home? Has anyone been in the same situation?



Would a wire brush make this look bad? (the brush cannot reach all areas).

Would anyone recommend just sanding off the few rust spots and painting the whole thing? (scuff the non-rusted areas)

Or should I take this to a body shop and have it done by a pro?

(I can take more pics if needed)

[danf20bcb7]

glass bead it

[Raf99]

glass bead it

Thanks for the reply. I'm assuming a professional would do this? (same as sand blasting but with glass?)

[Raf99]

Does anyone else have any thoughts on the topic?

[drummerboy_jh]

I'm doing this when I get my a4 or a6 exhaust manifold...

http://www.amazon.com/Calyx-Cast-Exh.../dp/B003D0R426

There was also a product review in Import Tuner or something a few months ago on this..

[Raf99]

I'm doing this when I get my a4 or a6 exhaust manifold...

http://www.amazon.com/Calyx-Cast-Exh.../dp/B003D0R426

There was also a product review in Import Tuner or something a few months ago on this..

Thanks for the help.

[Sordz]

That doesn't look like cast iron. If you don't want to use it as it is then I'd either heat wrap it or have it ceramic coated. Normal paint won't last at the high temps.

[steelbluesleepR]

Agreed, that looks like welded mild steel. If you have a drill, get some rotary wire wheels and go to town then get the highest quality high-heat paint you can. Or, take it to a shop that can put a jet-hot coating on it, they will prep it for you.

Don't touch the mating surfaces where it meets the head or turbo, though, that needs to be perfectly flat bare metal or it will leak.

[Raf99]

Thanks and thanks. I think you are right about the mild steel. I'm not certain how I would find out. I'll try the rotary wire brush too.

[steelbluesleepR]

Thanks and thanks. I think you are right about the mild steel. I'm not certain how I would find out. I'll try the rotary wire brush too.

Well, it appears to be welded, and it is very difficult to weld cast metals, particularly cast iron. Cast parts are also rarely in neat, tubular shape like that, the casting process dictates thicker, lumpier shapes.

[Raf99]

Well, it appears to be welded, and it is very difficult to weld cast metals, particularly cast iron. Cast parts are also rarely in neat, tubular shape like that, the casting process dictates thicker, lumpier shapes.

I see what you mean. I was thinking of cast iron hot water heaters (seen in old homes), but they are made from a mold I believe. / Where mild steel would be welded together in tubular sections¿ So for this pic I can see where it was welded together but the weld points are indented which I thought was weird. A wire brush should clean this unit up nicely then.

[Raf99]

And thanks for the help. I appreciate it and this is the info I was looking for. I thought this topic was dead last week.

[steelbluesleepR]

I see what you mean. I was thinking of cast iron hot water heaters (seen in old homes), but they are made from a mold I believe. / Where mild steel would be welded together in tubular sections¿ So for this pic I can see where it was welded together but the weld points are indented which I thought was weird. A wire brush should clean this unit up nicely then.

Yeah, the indented welds had me confused too. The rotary wire wheels I suggested are the same thing as a normal wire brush, just quicker and less tiring to use. They come in lots of shapes and different abrasive strengths so you can switch it up and use the best tool for the job.

[Raf99]

Indented welds pic

[GhostAccord]

yeah they definitely didn't use much filler on those welds. Looks like they did a root pass then forgot to put the cap on it....lol Could always have a welder run another pass over it if your worried about it.