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Sat Nov 08, 2025 4:16 pm

Any estimates on what the max or typical high temps of the metal are for a doghouse fan shroud on a 1600?

1 - my daughter wants to paint hers. I'm guessing this doesn't need to be "high temp" paint like a block would need, however I worry that typical paints would not last...?

2 - I intend to 3d print some various custom fixtures and clips for holding things, a fuel regular bracket, etc. I'm very familiar with the material science of FDM printing and will target what I use appropriately.
Do people get away with typical ABS? (Glass softening temp is ~100 C, 212 F). Obviously PLA is out, but I worry even about CF-reinforced PETG etc.
Worst case I'll move up to more complex materials, but I'm a fan of PCTG bc of its oil resistance.

3 - I'm assuming the lower tins over and around the exhaust get a lot hotter, and should be a typical high temp/ceramic paint?

Sat Nov 08, 2025 8:09 pm

Metal temp will depend how close/far from the block you are. But I'd say under 100c.

I printed some spark plug clips out of regular PETG and haven't had an issue. But my climate is somewhat mild.

Sat Nov 08, 2025 11:44 pm

I've painted the tin using regular automotive paint (to match the body for example) without any problems. Single stage urethane would probably work best. If you're using spray cans, I would get brand name engine enamel as it seems to last longer - I even use it on brake calipers.

Sun Nov 09, 2025 12:39 am

I used Rustoleum black spray paint on my fan shroud, and it looked and held up fine until the day I sold the car. That means it looked great for a good ten years, and I suspect it still looks good with the new owner. No bubbles, no fading, etc.

You do have to sand it down (at least enough to degloss) a little before spraying, of course, just like painting any metal surface.

Tim

Sun Nov 09, 2025 5:01 am

Like Tim said if you want the paint to look good and last you need to do the prep which is cleaning well first to remove any grease, and sanding with a fine grit before you paint. If using spray cans I always use krylon or Rust-Oleum with good results.

Sun Nov 09, 2025 7:53 pm

Thanks guys. Sounds like I'm overthinking this.

This is my daughter(15)'s project, so she wants to not only paint the shroud a pink shade but add some sparkle and she likes the look of texture... so the plan is (after primer) to paint it w/ Rustoleum Textured (which should hide the imperfections from rust etc) then pink over that, then her extra design, then sparkle clear coat. We'll see... its a case of "gotta let the girl do her thing and learn what works" I think.

Mon Nov 10, 2025 12:30 am

RatLabGuy wrote: Thanks guys. Sounds like I'm overthinking this.

This is my daughter(15)'s project, so she wants to not only paint the shroud a pink shade but add some sparkle and she likes the look of texture... so the plan is (after primer) to paint it w/ Rustoleum Textured (which should hide the imperfections from rust etc) then pink over that, then her extra design, then sparkle clear coat. We'll see... its a case of "gotta let the girl do her thing and learn what works" I think.

This is a problematic plan. Mainly because you're going to get too much buildup of paint thickness that will cause problems where the tin slides into other pieces, but also increases the possibility of cracking in the future. What kind of design is she planning?

Mon Nov 10, 2025 6:47 am

Keep in mind that engine compartments are hottest after the engine is shut off.

Mon Nov 10, 2025 12:53 pm

Tha Driver wrote: RatLabGuy wrote: Thanks guys. Sounds like I'm overthinking this.

This is my daughter(15)'s project, so she wants to not only paint the shroud a pink shade but add some sparkle and she likes the look of texture... so the plan is (after primer) to paint it w/ Rustoleum Textured (which should hide the imperfections from rust etc) then pink over that, then her extra design, then sparkle clear coat. We'll see... its a case of "gotta let the girl do her thing and learn what works" I think.

This is a problematic plan. Mainly because you're going to get too much buildup of paint thickness that will cause problems where the tin slides into other pieces, but also increases the possibility of cracking in the future. What kind of design is she planning?

Its only the main fan shroud that will have the extra layer of pink + coating. I can tape off the base lip where it slips into the other tins if its really that big of a deal.

For the design on top of the pink.... no idea. Maybe something hand-drawn, maybe she'll recruit my wife and here Circut to make a stencil.. or even vinyl s decals (which I don't know will have issues from the heat?).
This is 15 y/o girl wanting to do 15 y/o girl things, my job is to ensure it gets done in a manner that's not likely to severely mess something up and hope she learns something.

Mon Nov 10, 2025 12:55 pm

RWK wrote: Keep in mind that engine compartments are hottest after the engine is shut off.
Yep, this is where my concern is. I have no idea what that heat level is.

I guess what I'm really looking for is just evidence of what people have gotten away with, and hoping that if I have the tins and exhaust done properly there's some thermal barrier between the top and bottom.

Thu Nov 13, 2025 11:15 pm

First, I would forget the texture finish - just too thick & you might have a problem with the top coats sticking.
Ask her what kind of design she has in mind. I've been doing custom paint on show cars for over 50 years so I might be able to help. :)

Fri Nov 21, 2025 8:35 pm

Tha Driver wrote: First, I would forget the texture finish - just too thick & you might have a problem with the top coats sticking.
Ask her what kind of design she has in mind. I've been doing custom paint on show cars for over 50 years so I might be able to help. :)

I believe she's wanting to hand-paint a black spiral on top of the pink. Probably spiraling out from left of center where the more open portion is.

We already did the texture then pink (just Rustoleum spray) and honestly it came out looking pretty nice. Its just enough stipple finish that it hides 99% of the imperfections from where it was rusty, scratched and such.

It didn't add much thickness at all, I'll be pretty surprised if it has any effect on fit.

So the question now is, for the hand-painted part... since she just wants to brush it on, would an acrylic paint last?
It will get a sprayed topcoat afterwards and plenty of time to cure (weeks) before it will get hot first time.

Wed Nov 26, 2025 6:20 am

As a general rule, it's not a good idea to mix different paint types. You need to do a test panel if you're experimenting - & as a practice for things you haven't done before.