help me diagnose this paint problem

[jmitro]

this is from a 78 Porsche 911 SC I recently purchased. The car's shell is galvanized and the car is a southern car so rust shouldn't be a major issue. But the car has been repainted, and in multiple areas it has an orange peel appearance. It's most prevalent on the left rear fender and the right door, but in other areas as well. I know the photos are not great, but does this look like rust? Or simply poor prepwork before paint? This is a crosspost from another forum, and I've received mixed opinions about the underlying defect.

[962porsche]

all that is is a real bad spot of fish eyes . it looks like an oil was there eather from a hand print or some other oil type contaminant and it was not pre paint cleaned in the proper manner . but no its not rust its an oil based contaminant the only way to repair it is to sand it down spot prime , blend the color and clear the panel then color sand and buff . 500 or 600 dollars should fix it ??

[jmitro]

thanks.
Problem is, there are multiple patches like this all over the car. The only way to really eliminate them would be repaint the whole car.

from 8ft the car doesn't look too bad. only up close. i'll probably leave it for now.

[Canuck_Targa]

The first one definitely looks like a contamination problem caused the fish eyes. The second picture looks like surface rust forming below the paint (very common where I live), but the big patch on the rear quarter looks similar to what I saw on another car and it turned out to be bad glazing putty. Just the pattern of it looks funny. It almost looks like someone wiped down some spots with a rag that had a silicone contaminate on it. Since the car has been painted, there is a chance that there are areas that had some bodywork on them, and if the person doing the sanding is too aggressive they grind or sand the galvanizing off the metal, it is a very thin coating.

Just means you have to drive it more, if you are always moving they can't see them.

[962porsche]

you will get spots looking like that when you are wiping the car down with a pre cleaner and you don't wipe it off before it drys on the panel . when you pre clean a panel for paint you do it in a one foot by one foot area at a time . wiping with one rag soaked with pre cleaner and a good hand full of dry clean rags in the other . you then soak the 1'x 1' area with the wet rag with per cleaner and before the pre cleaner drys on the panel it must be wiped off . if it is not you will get wipe marks looking like that if there were any contaminants on the panel . the contaminants soffen and smug on the panel from the pre cleaner so what looks like grinding marks are realy wipe down marks .

[Bob Kontak]

Originally Posted by 962porsche

you will get spots looking like that when you are wiping the car down with a pre cleaner and you don't wipe it off before it drys on the panel

25 years I have been hobby painting cars and every time I read one of 962Porsche's comments I learn that I am still a learner. Those marks do look like wipe marks.

I'll go along with Canuck_Targa's vote of rust on the second pic.

[jmitro]

thanks for the replies.
i haven't had a professional examine the car in person yet.
I tend to think more and more since these spots are only limited to this fender and the driver door, that it's poor prep and not rust.
we'll see...