LT1driver

sprinklers came on car and left hard water water spots on my basecoat/clear coat ... mcquires paint cleaner did not work, nor did clay bar, or scratch x compound....help .. sat overnight and thru day with 100 degree heat before I came back and saw it

BarryK

The paint cleaner is not going to be aggressive enough for hard water spots and neither is ScratchX most likely.
i'd go with Ultimate Compound, or better yet M105 compound.
If you have a DA or rotary buffer it will make the work a lot easier but if not it should till be do-able by hand just with a lot more effort.
If working by hand work in small areas approx 1'x1', apply the compound with a foam applicator pad and really work it. It very well may take more than one pass to remove the marks even with compounds as aggressive as UC or M105.
I'd follow up the UC or M105 with M205 Polish than finish with your favorite wax or sealant

427lab

This happened to me with my new black Mercedes several years ago. I statred with the polishers and wax and quickly saw nothing was working very easily. Out of frustration, I just put some CLR on a rag, wiped it on and then washed it off. The spots disappeared immediately and the finish was back to new.

MikeM

Put some vinegar on a rag and see if the spots will wipe off.

Plasticman

While I agree that you should try the CLR or vinegar.

However if you see any depth to the spots (especially at the edges), buffing (or probably fine grit sanding and then buffing) is the next step. The combination of caustic minerals (from the water sprinkler source) and sun induced (magnifying glass effect) etching can really do damage!

Have a pro look at it.

Plasticman

66BlkBB

Clr ?????? What is it?

Plasticman

CLR is a grocery and/or hardware store cleaner for removing Calcium, Lime, and Rust spots (note the first letters in each of those deposits).

Plasticman

redred65cpe

Depending on the water spot (e.g. acidic) or for things like bird crap that bake on clear coat in the summer, it will not completely wipe off with any type of aid that I've tried. If you have a decent paint job you should have no problem doing a light wet sand with 1200 or 1500 grit followed up with fine polish (and then maybe glaze) and then wax. I do it all the time on my "regular" day-to-day car. Sometimes it just takes too long to get it out with just polish, hence the sandpaper. For a "big" job, I wouldn't trust myself using anything mechanical to do the buffing or sanding - I have nothing I want to practice on. In this case I'd take it to a trustworthy body shop or detailer.

larry

Powershift

Contains glycolic and sulfamic acids along with other miscellaneous/minor chemicals. Water based.

I would approach carefully for using on my car finish.....maybe test a few other painted surfaces around the house or garage to first get a better idea how it reacts and how quickly it must be removed. I would also be sure surface is cool rather than hot/warm.

As Mike M says, vinegar would probably be much safer and should also work.

Larry

ragtopman

...providing that all its done is left a spot in the clear, and Meguiar's still make it, I always had good luck with good ole #2 and a foam pad.

54greg

I've had success with dawn dishwashing soap-full strength- rubbed directly on panels and massaged in with your hands. Let it sit for a moments and rub off with water. It will get off just about anything. Follow with cleaner wax and I have been very successful in removing baked on water spots and never hurting the paint

OldKarz