markjmills

I've read the detailing forum threads, but none of them addressed my problem with a streaky rear window...and this is a much more active forum anyway, so maybe people here can provide some guidance.

There are cloudy (milky?) streaks on the exterior of my rear window that just will not be obliterated. Following the advice on threads in the detailing forum, I've used distilled water, isopropyl alcohol, Stoner's Invisible Glass, lint-free paper towels, microfiber cloths, clean soft cotton cloths, and so on. Many cleanings over many days - and still the streaks persist. In the past I've applied RainX to the window, but I don't think that could be the cause, as I've applied it at various times to all of the exterior window surfaces, yet only the rear suffers this problem. Has anyone ever had a similar problem and found a solution? What could possibly be causing this problem?

Thanks, Mark

Saijin_Naib

Try some acetone on a rag. Don't let it touch the metal trimming or the paint.

RBYCC

First try the old vinegar and newspaper method which was used for many, many years prior to the development of window cleaners that don't clean !!

If that doesn't work then apply a cleaner wax to the window..
The slight abrasive in the cleaner wax should remove any streaking...

Cleaner wax is a good method on all windows except the windshield.. !

190E 16V

Mark, do the streaks follow the embedded defogger wires in the window
Sometimes the layers of glass delaminate around the wires, looking "milky".
My car has started to do that at the edges. Others have had this problem too.

Kestas

Been there. I've been able to cure all minor ills on my windshields with glass polish (cerium oxide). I got mine from JC Whitney. The kit includes a felt polishing pad, but I use the compound by hand. I've even had stains on new windshields that needed this treatment.

The newspaper trick doesn't work anymore since they went away from the old inks (which were actually fine abrasive media) to soy based inks.

markjmills

I like the notion of using acetone, Saijin - mo' bettah chemicals to attack the streaks. But 190E's comment on glass delamination has me concerned; I can't really tell if the streaks are associated with the embedded defroster wires as my cleaning attempts have spread the cloudiness across the window, but his comment may pinpoint the source, which raises concerns. If the glass is delaminating and releasing whatever it is (adhesives?) that causes the streaks, might not acetone worsen the problem? Maybe the cleaner wax or cerium oxide might be the safer alternatives, not attacking the glass (and/or adhesive) quite so aggressively?

RBYCC, if I try using vinegar (I assume the white kind from grocery stores), is newspaper a necessary part of that technique? All of my local papers use the newer soy-based inks, so the older abrasive ink isn't available. Could vinegar just be applied wth a cotton cloth? If so, I could hold my nose and try that out...as long as my car doesn't smell like a salad!

Saijin, did you actually use acetone for a similar problem? Any issues with it hastening delamination?

Thanks to everyone for helping out!

RHW

Kestas, thanks for that suggestion.

Saijin_Naib

No, not personally on my car, but it was used on my father's 500e and our c280. The issue is that it can cause some damage to clear coats on the paint and stain the hematite trimming around the windows edge, so you really need to be quite careful when you apply it and remove it.

Both cars had a serious film/fogging on the front and rear windshields, the acetone treatment cut through it quite easily and left the glass as clear as it could be.

Delamniation is a physical process that occurs between the two layers of glass. Unless you somehow managed to get the acetone between the two, I doubt seriously it could cause any harm that way.

I'd venture that you should try the other less... corrosive treatments before you try this. Its a great last resort, but there are other treatments that should do the trick that carry less risk with them.

markjmills

I cleaned the window with white vinegar, using a clean soft towel, and miracle of miracles, it seems to have worked! I didn't rinse afterward, even with distilled water, fearing that any subsequent step was more likely to renew the problem. Of course I didn't really consider that vinegar, applied in a hot enclosed garage, would utterly destroy my olfactory sense. What we dislike in scents surely is very personal...but to my nose, vinegar is one of the foulest stenches on God's green earth. Baking in a vinegar-ridden hothouse of a garage overnight, I can only shudder to think what my baby will smell like tomorrow! I may be posting a new thread soon, pleading for help with exorcising the horrid pong.

RBYCC

Glad the vinegar worked...
Guess I'm out of touch with current newspaper inks...

If you want to neutralize the vinegar, wet a cloth and put a bit of baking soda on it..
Rub the window down and it should remove any of the acid residue left by the vinegar...