prepare engine manifold for painting

[FrankWest107]

My engine manifold on a 80 year old engine is rust color and I would like to prepare that for painting.

Any suggestions.

[pont35cpe]

Frank, just an idea.. I had my exhaust manifold for my `36 Buick and dual exhaust manifolds for a `41 Buick super engine I rebuilt, ceramic coated at a local powder coating business, they actually look like chrome and will hold up to the heat.. From my experience paint will eventually burn off... even the high heat paint.. Tom

[trimacar]

Bead or sand blast, if you're going to paint it with high temp paint.  Just make sure you go back and clean all the grit out from INSIDE the manifold, just to keep everything tidy.

 

You could also very carefully wire brush it, a brass brush will eliminate a lot of surface corrosion.

 

What you DON'T want to do is try to "pretty it up", say, by taking a grinder to it to smooth it down or knock off an ear you don't like.  Due to repeated heating and cooling, a cast iron manifold can develop a surface tension, and bothering that surface tension can sometimes make a manifold do a Rice Crispy imitation (snap, crackle, and.....so forth).

[Dave Henderson]

When a manifold has any threaded studs, such as on some Jaguar manifolds, put nuts on them to keep the threads from being destroyed by heat or getting coated over if going the porcelain enamel route. 

[joe_padavano]

My engine manifold on a 80 year old engine is rust color and I would like to prepare that for painting.

Any suggestions.

 

Intake or exhaust?  Iron or aluminum?  These answers will affect the proper process.  Assuming a cast iron intake:

 

1) Degrease thoroughly

2) Sandblast.  Do not touch the blasted intake with bare hands, as this will transfer skin oils to the metal.

3) Blow off any residual sand/dust with compressed air,  Some will heat an intake at this point to remove any residual oil or gasoline residue.

4) Wipe down with lacquer thinner using a lint-free rag

5) Prep and paint using your choice of engine enamel and that manufacturer's prep and primer recommendations.

[huptoy]

August of 2008, I had the intake & exhaust manifolds coated using their power coating process called "Armor Coating".

The exhaust has faded a little as shown in the the photo but the intake is as originally delivered.

I have driven the car 8,500 miles in the last 7 years.

 

Aesthers Finishes Inc

1502 S Main St

Piqua, Ohio

(937) 778-8860

 

http://www.afipowder.com/powder-coating-2/

Edited June 7, 2015 by huptoy (see edit history)

[JWLawrence]

For cast iron exhaust manifolds, I have had good results using Eastwood's gray cast iron paint. Thoroughtly clean and apply per directions. The gray finish looks like fresh cast iron. It is a durable finish and actually looks better with age.

 

(o{}o)

[Guest pehernan]

Something that I used for other parts is the electrolysis, I'm thinking that will be a good way to clean the interior and revert any corrosion in those area that are hard to reach with conventional methods (a brush or sandblasting)