Fan housing, What’s the best way to clean and paint one. Options

[Mikey914]

Cerikote is good stuff. Especially if it's baked on. You can argue the heat form the engine may do this, but I suspect that you will have zero issues with it, as long as the surface has no grease or crud on it. We use a acid pre treatment when we coat to get all imperfections off. Muriatic acid works well and is readily available. This will give you a finish that will not oxidize or stain easily. Aluminum is porous (especially castings), so the surface picks up crap easily.

[mepstein]

Cerikote is good stuff. Especially if it's baked on. You can argue the heat form the engine may do this, but I suspect that you will have zero issues with it, as long as the surface has no grease or crud on it. We use a acid pre treatment when we coat to get all imperfections off. Muriatic acid works well and is readily available. This will give you a finish that will not oxidize or stain easily. Aluminum is porous (especially castings), so the surface picks up crap easily.

The housing is mag. That's why a paint like cerikote is good. It' can be iffy trying to powdercoat mag.

Mahle gas burner wheels are mag and they were primed and painted. They would have looked pretty rough in a short time if left bare.

[DRPHIL914]

interesting information about the factory coating. i think just like today, with “lifetime no maintainence transmissions” etc the factory only wants to get past the warranty time as far as making it last. Maybe it was not the best way to go but i bought a fan housing that was cleaned and powdercoated and it looks great. i bought it from Mr. Stone and i still have my original one, i should clean it up but all the oild from the leaking crank seal and all the undercoating are probably protecting it from corrosion.
I guess i can just watch and see how it lasts. it looks great!

[jsaum]

I finally got back to this project. After looking at several of the suggested coatings I decided to just go with spray paint. It may flake off in a few years and if so I’ll go with something more durable. I used a lot of degreaser, oven cleaner and muriatic acid to get the surface clean. I the sanded it down with 100 to 200 grit sand paper. I’m happy with th e way it turned out.

[jsaum]

Here’s more pictures.

[Spoke]

Looks good.

Remember to scratch off the paint where the 4 bolts from the engine mount the fan housing onto the engine case. This is the return (ground) path for the alternator. Also scratch off the paint where the alternator bolts to the housing.

[DRPHIL914]

Looks good.

Remember to scratch off the paint where the 4 bolts from the engine mount the fan housing onto the engine case. This is the return (ground) path for the alternator. Also scratch off the paint where the alternator bolts to the housing.

(IMG:style_emoticons/default/agree.gif)
I made that mistake and slowly saw my voltage drop over a 4 hour drive and almost didn’t get home!
That does look great though!

[nathanxnathan]

I bead blasted 2 fan housings, and they looked pristine bare.

1 I coated with crc corrosion inhibitor which gave it what I think looked like a factory finish, a sort of golden coat of wax/oil. It's been on a shelf for a few years and it's darkened about comparable to a factory finish. Never actually ran it though.

The other I put installed bare and noticed it was oxidizing, some white rust on the top. I decided to rub motor oil on it, and I think it actually worked pretty well.

[porschetub]

Looks good.

Remember to scratch off the paint where the 4 bolts from the engine mount the fan housing onto the engine case. This is the return (ground) path for the alternator. Also scratch off the paint where the alternator bolts to the housing.

Oh dear never thought about that,could that explain why I have had issues with electronic ignition modules,probably not but thought I would ask (IMG:style_emoticons/default/confused24.gif) .

[jsaum]

Thanks for the reminder. I figured it would need to ground so I removed the paint at the parting line of each case half and do plan to remove the paint at the mounting points so I’ll have a good ground. I used my ohm meter to check to make sure there is no resistance on the ground tab at the top. So far so good.

[bdstone914]

What heat dissipation is there on a cool air shroud?
I have sand blasted them and sprayed with silver metallic. The mag will soon tarnish soon.

[mepstein]

What heat dissipation is there on a cool air shroud? --- None. The heat dissipation isn't a thing with the shroud. Guys aren't really thinking on this one.

I have sand blasted them and sprayed with silver metallic. The mag will soon tarnish soon. ---Porsche had the magnesium gas burners primered and painted so they would look nice. The same can be done with the fan shroud. I would use a two part paint if you want it to last.