GT40 Valve Covers - Paint won't come off

So I'm getting ready to reassemble my GT40 next week...block is back from the rebuilder.

I am fixing up everything that will go onto the block so it all looks new. Por-15 is going on exhaust risers, engine enamel on everything else.

I've decided to paint the valve covers Ford Racing Red. I wanted them to look good so I thought I'd do them right. I planned to strip them to metal, prime with zinc chromate and paint from there to look amazing.

I started on Saturday with the cover with the oil neck. I bought an aerosol can of automotive paint stripper from the local box store. After the entire bottle, 24 hours, and lots of sitting a scrapping and even sanding, the paint wasn't barely scratched.

I've painted cars before, its been 15 years, but I knew I needed proper stripper. So I called the local body shop supply store who is still open for curb-side pickup due to the virus. Ordered a quart of Aircraft Stripper and some cheap brushes. Pulled up and they dropped the box in the bed of the truck. (I really like shopping this new way due to the virus!)

Yesterday I got to work. I put a thick coat of the stripper on painting only one direction and as minimally as possible (per instructions). Can said to wait 10-60 mins. After 15 mins I started to notice some minor paint blistering. Yay. I went away for an hour and came back to find some more blistering but not near as much as I had expected. I took a green scour pad and went to work.

For the paint that blistered, I was able to to remove it to the metal. But only about 20% of the paint removed. At this point I used the green scour pad to really scrub on the paint and to try to at least penetrate the surface. I cleaned it up and re-applied more stripper.

I have now gone through this process 6 times. A few times I have let the stripper sit for hours.

I am 90% there, but I am completely perplexed. I've never seen any paint this hard to remove. There was a minor paint run on one side of the cover, so I am assuming someone else has painted these in the past. There was no yellow or grey primer, so I don't think they were epoxy or zinc chromate painted. I'm regretting I ever started to strip. I am absolutely NOT stripping the other cover.

So here are my questions....
1) Has anyone seen this before. The paint job seems amazing. I'm sad I removed it. I think it was impenetrable.

2) I have attached pics of the current status. There are still areas that have some paint that show no signs of blistering. I'm thinking of sanding these smooth and leaving under the new primer. Am I crazy?

3) Was there a better way to do this? I wanted to ensure a quality bond for the new paint and everyone here in other posts says to strip to ensure you get oil soaked paint off.

That’s a lot of work for stamped steel valve covers...

There is a chance that the covers were powder coated. If so, you are trying to remove a thermal plastic.

gun-driver wrote: Not sure why you want to paint them red when black looks soooo good. As for the paint I believe they may be baked on enamel.

Wow Gun...that engine is gorgeous. I agree black looks good but I wanted some contrast. Through the red valve covers would offer some pop. Also, I've got new spark wires that are grey. I like your red wires!

Is the GT40 Pro Boss valve cover logo strip new? Mine is acceptable, but a new one would look amazing. I didn't see it on nautiqueparts. Any lead where to get a new one?

So I stayed up until 3 am last night and got enough of the black paint off to start priming. What's funny is that the other valve cover had some rust along the edges and peeling paint. I think that stripping it would have been easy, but I sanded instead. I uncovered all the rust on it and used my dremel with a polishing bit to grind all the rust off and get it smooth.

Here are some pics:

gun-driver wrote: Those are the original decals, i don’t remember seeing them available anywhere.

Did you take yours off when you repainted? If so, what did you use as adhesive when you reinstalled?

Painting project all done!

Was a lot of work for sure, but I'm glad its done right. All of the black cast has Por15 using the 3 step process. Stamped pieces have Duplicolor High Heat Engine Enamel. Everything has been baked at 300 F for 2 hours on the gas grill outside.

Happiest person is my wife. She was getting testy about the paint fumes.

Word of caution to others...on my second valve cover, I put an additional coat of red about 2 hours before I baked it. Big mistake, paint blistered badly within about 10 mins in heat. Had to strip it and start from scratch. Let the engine enamel cure overnight before baking. Round 2 worked fine.

That’s a purdy engine. Can’t go wrong with RED

JQ

I blasted mine Paul,I think they have a thin grey or silver on them originally.

Gary S wrote: I blasted mine Paul,I think they have a thin grey or silver on them originally.

Yea I believe they do, I always thought cleared clean aluminum would look good.