Stained Bumper

[Big_Tone]

Hey guys. Since buying my car (pre-owned) there have been what appear to be dirt stains in the rear bumper that I cannot get off. I’ve tried the clay bar, which did wonders on the rest of the car, but had no effect on the stains. Has anyone else had this problem? If so, how did you remove it?

[Ilya]

Where on the bumper? If it's lower by the exhaust, I don't know how to get rid of that...I have it too lol.

[Big_Tone]

No, I’m not talking about that. I’ll try to remember to take a pic during the daytime, but try to picture what a car looks like after it rains. You know how there will be streams of water and/or dirt on the sides of the car? That’s what the dirt looks like on my bumper. It doesn’t look horrible, but bad enough for me to notice.

[GMBQ70]

Hmmm... would like to see pics of this to know what we’re dealing with.
Thanks

[pedsemdoc]

Hmmm... would like to see pics of this to know what we’re dealing with.

I agree, and if a clay bar didn't make a difference, it sounds like the stain is deeper...maybe try rubbing compound/3000 grit wet sanding???

[Big_Tone]

Here's a pic. Where there appear to be lines in the pic are stains that won't come off...

[GMBQ70]

Well, I’m no expert, but that looks like hard water stains. There’s a product you can purchase to remove the stains, from “Chemical Guys” and I also found a method using vinegar and water mixture. I would like to see others opinions on the forum, before you move forward with any products, that could cause damage to the paint.
If it is hard ward stains - below are some removal methods that I found from Adams Car Polishes.


REMOVAL METHODS:
These processes are listed in order from least to most aggressive.

Start simple! For lighter spots something as simple as a complete wash or wipe down with Waterless Wash or Detail Spray and a microfiber towel may be enough to remedy the problem. As with any detailing process, always try the least aggressive/simplest method first.
White vinegar can be used for spots that are a little more stubborn and more mineral based. Soak a small area of a plush microfiber towel with the vinegar and wipe the problem area (after the area has been properly cleaned and dust removed) Perform this task out of direct sunlight to avoid complications. Be sure to reapply your preferred wax/sealant to the area as the vinegar will have degraded/removed any protection.
Claying can be very effective at removing water spots. The process remains unchanged from the usual claying process. Adequately lubricate the surface and move the clay back and forth over the area. Be sure to spend extra time working the spots from multiple angles to give the clay the best opportunity to grab the contamination. Repeat uses may be needed in some cases.
If the prior step fails to completely remove the spot then you may be dealing with etching. In this case physical abrasion of the surface becomes necessary to 'level' the clear coat back to the same as the surrounding areas. Follow the same guidelines as when polishing to remove swirls, be sure to use the least aggressive polish to get the job done and always test your process in a 2'x2' area before completing the entire car.

[Big_Tone]

Thanks for the tips. I may try claying again this spring. The last time I tried it, it didn't work.