Acrylic Enamel Paint for Engine?

[Ryban]

I'll be re-painting our engine when I pull it out to paint the engine room, replace the engine mounts, as well as do some maintenance on the engine itself.

I've got the color code from the manufacturer, RAL1007 (European code), and I can easily find acrylic enamel paints in this color, but are they suitable for our engines? Presumably yes, given that the temperatures our engines achieve are not extreme, but I can't find spec data on the paint for what it can tolerate.

https://www.lvppaints.com/RAL-1007-1...-Up-Paint.html

[Tin Tin]

Page 2 of the spec sheet, 180F.
Specific engine enamels are around 550F

[Ryban]

Originally Posted by Tin Tin

Page 2 of the spec sheet, 180F.
Specific engine enamels are around 550F

That seems to be the max temperature when using a heat gun or similar to force dry the paint, not the maximum temperature the cured paint will tolerate.

[Khaos13]

I use an airbrush to paint engines. I'm painting my Westerbeke 21A right now using Rustoleum Gloss White over a zinc chromate primer. I starting using the airbrush years ago in my days as a yacht engineer. Most yacht engines (in my experience) are delivered to the builder painted gloss white. With routine maintenance, bolt heads and small parts get nicked and chipped and the airbrush is the perfect tool. On yachts I used Awlgrip Matterhorn White, about $400 a gallon with reducers and catalysts. You don't need much. Sure, on exhaust parts you can get some discoloring but otherwise normal engine temps stay looking good for years. The great thing about the airbrush is you can do touch ups without masking; you can be very precise or spray a 2" wide pattern. You can lightly fog the color on in a pencil point too. Just my $.02

[Ryban]

Originally Posted by Khaos13

I use an airbrush to paint engines. I'm painting my Westerbeke 21A right now using Rustoleum Gloss White over a zinc chromate primer. I starting using the airbrush years ago in my days as a yacht engineer. Most yacht engines (in my experience) are delivered to the builder painted gloss white. With routine maintenance, bolt heads and small parts get nicked and chipped and the airbrush is the perfect tool. On yachts I used Awlgrip Matterhorn White, about $400 a gallon with reducers and catalysts. You don't need much. Sure, on exhaust parts you can get some discoloring but otherwise normal engine temps stay looking good for years. The great thing about the airbrush is you can do touch ups without masking; you can be very precise or spray a 2" wide pattern. You can lightly fog the color on in a pencil point too. Just my $.02

That's interesting! Air brush does seem like a good way to go for precision, over a rattle can, that's for sure. You said you use Awlgrip on yachts but are using Rust-Oleum on your own engine? Any reason for this, or just cost?

I wasn't planning on changing the color, but white does have a certain appeal to it, especially when it comes to finding leaks.

[Khaos13]

Most yachts, (again in my limited experience) are painted with Awlgrip Matterhorn White. It's a tradition. We always seemed to have it around. It's a linear polyurethane and has great UV protection qualities. You can't buff it or blend it however, because the clear, UV protectant rises to the top. If you buff thru it to blend in a patch it will "halo" within a few months in the sun. For engine painting, it was really a matter of convenience and continuity and you can't use rattle cans. Half pint cans of Rustoleum cost about 15 bucks. A half ounce goes a LONG way. I thin it with Acetone and some folks add a catalyst or hardener. Rustoleum will always be around and it's cheap. Fast, cheap & easy... that's me!