I need some advice on how to handle a stain on my hood. This is a 2002 911. I had it out at a track day and had to apply numbers to the hood and doors. I used SoloTime removable vinyl decals with a 'low tack' adhesive. It was raining that day, so some water got trapped under the numbers. Upon removal, 2 of the 3 numbers on the hood left behind heavy water spot stains (no problem with the doors). My guess is that some combo of the water and adhesive caused the stain as the sun came out in the afternoon.

Anyway, I've washed and scrubbed the car. I tried using a cleaner wax and clay bar on the spots with no noticeable improvement. This was all done by hand, using progressively firmer pressure as no impact was made. The stains are not rasied above the surface and cannot be felt. It seems they have penetrated the clear coat. You can get an idea of the problem from the pics.

Now, I don't know what to do. Your suggestions would be appreciated.
1 - try an orbital or other product on my own.
2 - get a pro detailer to take a shot
3 - just have the hood repainted (I've got some road rash on the front bumper and hood that also needs to be addressed.)

Thank you in advance.

 

That might need a repaint, but if you can find a very good detailer in your area that could wetsand it out that would be your best bet.



John

 

What exactly was the adhesive that you used?

That is very odd that it would penetrate the paint that bad and that fast... I would also suggest taking it to some high quality detailer to first try polishing with a rotary and see if that does anything, then maybe wetsand... good luck

 

I don't know what the adhesive was. They were pre-printed numbers with the adhesive backing already applied and explicitly intended for this use. I've contacted the manufacturer to see if they have any explanation.

 

Looking at it via web pictures it looks like....

There was a fairly strong VDS used in the adhesive. Heptane, xylene, acetone, etc. That penetrated the porous structure of the clear and separated the layers. It may not be something you can wetsand out.

 

Just let it sit out in the sun for a week or so. It seems that there's moisture in the clear and it will eventually dry out. If it doesn't, you may need a repaint.

 

Strange incident indeed.

Maybe the clear had some sort of chemical reaction to the mixture of the adhesive, water and heat from the sun.....

Can you feel it at all? Does if feel ruff or smooth? Is there any texture to it at all? Is it etched in like a harsh water spot or bird dropping?

Need more info, the pics are good but not enough.

I would try something like an adhesive remover first, then step up to polishing and then wetsanding before talking about a repaint. Exhaust all your options first.

If I was your detailer, I'd hate that kind of situation as you'll have to pay for his time with no promise of results.....

Josh

 

That appears to be what is called moisture migration. I've seen and repaired that more times then I can remember on new audi's at a dealership I once worked at ( main reason audi's come in a cloth car cover now during transport). What happens is moisture gets between the sticker and paint and has either two placed to go, through the sticker or into the paint. It goes to the easiest route. Try a blow dryer on low heat to start in circular motions. That should do it. It not you can kick up the heat, but I warn you to be careful as it is very easy to damage the paint.

 

Moe & Master - your suggestions are exactly what the sticker mfg suggested to do. I left it out in the sun for a few hours with no change. I'll leave it out all day and then try the hairdryer if nothing else.

Thank you all for your suggestions.

 

Just curious to how you made out with your issue?

 

That is a very strange issue. It does look like a moisture issue, but if leaving it in the sun is ineffective it could be some type of paint staining due to a chemical reaction with the adhesive.

If the sun or heat doesn't fix the problem see if a pro can wetsand it out at all.

 

I've given it about a full day of sun, plus a few hours. I cannot see any improvement. I'm going to give it some more sun and try the hair dryer a little. At this point, I'm leaning toward a repaint of the hood and front bumper. I'll get rid of the spots and some road rash at the same time.
Thanks again for your help.

 

mathism, I just noticed you're in Chicago. I'm going out of town Fri-Mon but I'm willing to take a shot at fixing that with some clay, polish and then we can try wet sanding if you'd like, but at your own risk as I don't have enough experience to trust myself with clients' cars. I'll do the spot clay/polish for free since it shouldn't take more than 30-45 mins.

As I said, I'll be back in town Monday night, so I can find some free time pretty much any day after that.

Feel free to PM me here or call me, 773.715.4198. I tend to ignore all unknown #s, so just leave a msg and I'll get back to you right away.

Have a good memorial day 6speed, my bike and I are going to have some fun on the open curvy country Wisconsin roads for 4 days!!

 

Ivan - I really appreciate your offer. I've already hit it with a clay bar, wax cleaner and polish to no effect. I don't think I want to do a wet sand. The more I look at the rest of the hood, the more I lean toward having it painted. It would be nice if these stains went away and I could wait another few months (damn property tax bill due in a few wks). Once it is painted, I need to have the whole car professionally detailed.

I'm headed to Lake Geneva for the wk end. If you buzz by a black 335 coupe or 911 with a foggy "50" on the hood, thow me a sign!

 

Bummer that it looks like its going to come down to a repaint, but hey, at least that will cure a lot of the other defects on the front bumper and the hood for you.

Got to have a silver lining somewhere...