100LL eating new paint

[Thedude]

I just got my plane back from the paint shop last week and it's beautiful. This did expose a slow leak and when I went back to look at the plane today it appears as though the paint bubbled and was eaten away. My understanding is that this was not normal for 100LL, can someone confirm that.

[Fix]

This looks more like there was an ongoing leak while it got painted, than if you compare with G100UL paint problems.

[201Steve]

Looks like there was a stain of fuel that accumulated between stripping/cleaning and actual painting. You can see around the screw head that the paint didn’t adhere from the fuel coating being present on the skin surface

[Thedude]

It didn't look like this when I picked it up though, it looked perfect. Would that still be an issue of the paint not adhearing because of a fuel coating?

Should the shop have noticed and done something about it?

Edited April 17 by Thedude

[EricJ]

+1 that that looks more like a prep issue.   An existing leak or two weren't cleaned up during the process.

[Slick Nick]

1 hour ago, Thedude said:

It didn't look like this when I picked it up though, it looked perfect. Would that still be an issue of the paint not adhearing because of a fuel coating?

Should the shop have noticed and done something about it?

Yes. They just painted over top of the issue, albeit probably not intentionally. It was only noticeable once the paint (which had nothing to adhere to) started flaking off. 

[PT20J]

Polyurethane takes up to 30 days to fully cure, so new paint will be more vulnerable. I’d take it back to the paint shop. A quality shop will want to fix it. Resealing an access panel  to fix the seep isn’t difficult. I just had one of mine done in preparation for painting. Then they can fix the paint.

[Fritz1]

minor leak that nobody noticed, easy to fix, white paint easy to blend, work it out with the paint shop, they overlooked the leak so the paint is on their dime, the leak is on your dime unless they want to take responsibility because they overlooked it, chances are remote that this leak was caused by paint stripper

[Schllc]

I literally had nightmares about this scenario and I did not have any active leaks, nor history of them.  I waffled for a few months to reseal or not  

I eventually gave in and they are getting sealed right now, paint to follow as soon as they are done  

 

[Thedude]

I've emailed the shop, they're a 10 minute flight away, so conviently close, but I don't want my plane down for longer  Either way thanks for the insight

[EricJ]

4 hours ago, Schllc said:

I eventually gave in and they are getting sealed right now, paint to follow as soon as they are done  

It seems a dilemna whether to reseal before or after paint.    The reseal strip might damage the paint, and the paint strip might damage the reseal.

[Schllc]

Damned if you do….

[shawnd]

On 4/18/2025 at 3:03 AM, EricJ said:

It seems a dilemna whether to reseal before or after paint.    The reseal strip might damage the paint, and the paint strip might damage the reseal.

I would imagine you want to reseal, let it cure for a while and then paint and then let that cure. This is the general advice I have been given by many and was my plan of action once my plane visits MN.  Not sure about how long to wait after resealing tanks but I am sure someone can chime in. 
 

What in the tank sealant can cause paint to get damaged if cured properly?

[PT20J]

According to RPM Technologies, PolyGone (chemical used to remove tank sealant for a reseal) will attack paint and primer.

A lot of MSers have had tanks stripped for resealing using the recirculating stripper technique. I'm curious what your experience was with respect to damaging the paint.

[Marc_B]

I had my tanks resealed. All of the fuel access panels are opened and were previously covered in original paint with original screws. I don’t think that reseal is so damaging as much as you can tell those panels have been opened and touch up paint never looks completely like original. But the paint is only affected on the panel seams and screw heads. 

[1980Mooney]

On 4/17/2025 at 7:52 AM, Thedude said:

It didn't look like this when I picked it up though, it looked perfect. Would that still be an issue of the paint not adhearing because of a fuel coating?

Should the shop have noticed and done something about it?

There are other factors not mentioned.  What is the location of that panel and how much fuel was in the tank when you had it painted?  I bet your tanks were low when painted (and no seeping) and it appeared when you filled the tank full - more head, more pressure.

 

On 4/17/2025 at 11:46 AM, Thedude said:

I've emailed the shop, they're a 10 minute flight away, so conviently close, but I don't want my plane down for longer  Either way thanks for the insight

In my limited experience, aircraft paint shops do not repair tank or panel leaks.  It sounds like you have two (2) trips/stops (and twice the down time) to get this corrected....

Edited April 19 by 1980Mooney