My Compressor blew about 2 months ago and left oil stains on the under-hood. I didn't clean it off because I am going to do a lot of engine-bay work during the winter down time.
I do not notice any bleed through to my paint. I have satin black enamel on the under hood area, 1/4 to 3/8 thick F.R.P., jelcoat, and then urethane paint on the top. I have never heard of this happening before.
I just went to the garage and used a little brake cleaner on the dried oil and it came right off.
Are there certain types of AC oils that would do this? I find no damage to my car.