Removing water stains on a white hull

[tmusky1]

Hey everyone, I'm a proud new owner of a 2002 Nitro that I picked up locally. Anyway, some of our smaller lakes resemble strong day-old coffee and have left a brown water stain/line on the white hull.
I have an orbital polisher I plan on using to remove it but most of my experience is with metal. Any fiberglass tips and/or product recommendations?

[Bodofish]

Oxalic acid, can't remember, its either hydrochloric or sulfuric... regardless, you can get the hull cleaners at what ever marine store you like. Watch out for hydrofluoric acid, it's extremely toxic it probably works the best of all of them but, make sure you are completely covered and have some sort of mask that can filter for it, organic fumes(?). Just my experience from detailing a couple hundred boats, the polishing comes after you get rid of the stains. If you have a white hulled boat, just pop for the 3M quart kit. For quickie jobs, I used to use the West Marine cleaner wax followed up with the West Marine Teflon wax. What ever you use, make sure the last step is the Teflon wax. It will last 6 Mo. to year on boat moored in salt water. Any scum will just rinse off. I use it on my truck too.

[tmusky1]

Thanks Bodofish, will it damage the rubber/plastic keel guard or paint on the trailer?

[Bodofish]

Thanks Bodofish, will it damage the rubber/plastic keel guard or paint on the trailer?

Probably won't hurt rubber and vinyl if used as directed but I sure wouldn't leave it on a trailer for any length of time.

[Larry3215]

You might want to try something safer first. If that works, then you dont need to use dangerous stuff or at least you might be able to use less of it.

Id try something like Simple Green or the Orange cleaners first, They will take a lot of it off and maybe even all of it.

Like Bodo aid, a hi quality wax will go a long ways towards keeping the stains from coming back.

Its a lot of work though. I learned to live with the stains on my old boat

[tmusky1]

We've got some Simple Green around the house somewhere, I'll give it a try first.Thanks

[hewesfisher]

Can also try a rag soaked with white vinegar to dissolve water spots. Non-toxic and cheap too.

[4n6fisher]

Stay away from Hydrofluoric acid, it is very toxic and will dissolve glass among other things, including eating through your skin and bones. Oxalic acid would is an organic bleaching acid (not hydrochloric or sulfuric), using a dilute solution (3-10%) of that would be my choice of the vinegar does not work. Any acid residues should be washed off and/or neutralized with baking soda so they do not attack other items.
As with any acid solution wear the appropriate safety gear (gloves, masks, glasses, etc.) and have good ventilation.

[Bodofish]

Stay away from Hydrofluoric acid, it is very toxic and will dissolve glass among other things, including eating through your skin and bones. Oxalic acid would is an organic bleaching acid (not hydrochloric or sulfuric), using a dilute solution (3-10%) of that would be my choice of the vinegar does not work. Any acid residues should be washed off and/or neutralized with baking soda so they do not attack other items.
As with any acid solution wear the appropriate safety gear (gloves, masks, glasses, etc.) and have good ventilation.

Went out an looked at the old jug of cement/wood/glass bleach It's labeled Oxalic Acid but also contains hydrochloric acid. I knew I saw that... I also looked at the other hull cleaner, the hydrofluoric acid stuff and the directions say to dilute it by quite a bit for use on glass, like 80%. Yes, it is very nasty stuff, I've never put it on fiber glass but it does work wonders on a metal hulls. BTW, it's about the only acid that can eat glass, it comes in a Nalgene bottle. That said, as stated earlier, use an appropriate breathing apparatus as the fumes can kill you in short order or cause irreversibly damage your liver and other endocrines. It's very nasty stuff, contact with your skin is as damaging and as fast as breathing it. Goes right through your skin. It is possibly the nastiest chemical you could come in contact with in a non industrial setting, with out going radioactive ( the only cyanide you will come in contact with is in a peach pit. And well there's arsenic too but...)

Oxalic is the best bet as it is hydrophilic in nature, it seeks out water (normally the stain). This is what I've used on many hulls and it does work. My bet is vinegar, simple green and citrus cleaner do nothing to the stain. What is it they saying about doing the same thing over and over expecting a different result... ?

Be careful.

[dutchman2858]

Orange cleaner in a spray bottle worked for me. Spray it on, give it a couple minutes, scrub with a brush and rinse. Cheap also. Simple Green should work well too.

[tmusky1]

Well, my son bought me a bottle of MaryKate On And Off. That stuff works great. The boat looks brand new!

[Sideburns]

Glad it worked out for you...

Just thought I'd mention my frustrating experience with rv water stain remover... Destroyed my windshield! etched it badly, even though I thought I was being cautious with it. The rinse water that quickly ran over all my windows left cloudy etched streaks . Took several attempts, and many hours to polish the glass with cerium oxide. In the end, i polished /removed too much glass and caused a lens effect that now distorts the view out of the window! good times