Brown mustache

[lspringer]

My wife and I regularly cruise the AICW. We repeatedly acquire a brown mustache on our bow. It comes off easily with either FSR or ON-OFF but then comes right back. Waxing does not seem to impede the process. Often it comes back in streaked patterns indicating that the removal process has an effect on its return. Our hull finish is white Awlgrip.

Does anyone have any suggestions for eliminating, or at least lessening, the recurrence?

Thanks for any suggestions.

[billknny]

Not much to do...

You already have the best cleaning protocol I know of. I'd skip the On-Off, it's more aggressive than needed and could damage your Awlgrip. You can save a bunch of $$$ over FSR and simply use pure Oxalic acid. Make a thin paste, wipe it on, sit for an hour, wash well, rewax.

While caring for a large charter fleet I saw that on identical boats, used similarly, native gelcoat was MUCH more susceptible to brown waterline stain than Awlgriped boats. I assume the gelcoat was a bit more porous...

[Dsanduril]

FWIW, a brown mustache on inland waters is usually tannins (think tea) from trees and other vegetation getting into the waterway and decaying. Quite common here in SE Alaska as well. Usually find it on the bow where the bow wave brings water above the waterline and gets to the gelcoat (it's also at the waterline, just harder to see on the bottom paint). Pretty much all of the tannin removal products are acids of one kind or another, and oxalic acid is usually effective and cheap.

[Cheechako]

It can be oil on the water often. It shows brown and is very hard to get out of gel coat.

As we were passing a French island in the Caribe once, an official looking large grey navy like boat was motoring around in a 1-2 mile circle, the water was very oily everywhere. They were obviously dumping a bunch of oil of some sort from the island. It must have been 100's of gallons. We were sailing through it for a 1-2 hours. It took forever to get that stuff off the hull. Not sure I ever really did. Cleaned and polished it off as best we could much later while stored in Trinidad.

[Delfin]

I have Awlgrip and while it is more resistant to browning that fiberglass, it still occurs. I mix Muriatic acid 1:4 and spray on with a cheap garden pump up sprayer. Wait 10 minutes and hose off. Mustache gone, no paint damage.

[GordMay]

Greetings and belated welcome aboard the CF, Ispringer.

Originally Posted by Dsanduril

FWIW, a brown mustache on inland waters is usually tannins (think tea) from trees and other vegetation getting into the waterway and decaying. Quite common here in SE Alaska as well. Usually find it on the bow where the bow wave brings water above the waterline and gets to the gelcoat (it's also at the waterline, just harder to see on the bottom paint). Pretty much all of the tannin removal products are acids of one kind or another, and oxalic acid is usually effective and cheap.

Indeed.

[roberttigar]

I clean my smile with lemon juice. Spritz it on, leave it for 10 min and hose off. Then do it a secont time...maybe even a 3rd. Lge bottle of lemonjuice from dollar store lasts quite a wehile.

[Aircool]

FSR will remove your protective wax,

If you use fsr you have to wax again right after. On my boat i put a good wax and the only use of soapy water remove the brown mustache ( I had an hudson/manhattan/ICW mustache to give you an idea)

[lspringer]

Many thanks to all who replied. I do find I made a mistake in my original post. my paint is Awlcraft, not Awlgrip. I will be sure to try the lemon juice suggestion.

[Delfin]

Originally Posted by lspringer

Many thanks to all who replied. I do find I made a mistake in my original post. my paint is Awlcraft, not Awlgrip. I will be sure to try the lemon juice suggestion.

Awlcraft has a little less chemical resistance to acid than Awlgrip, but still plenty enough for a few minutes exposure. I've found that the referenced dilution for muriatic acid certainly removes tannin stains, but doesn't take off the Awlcare sealer, which is kind of nice. If you did use that approach, do not get it on stainless steel. Doesn't hurt the ss, but it spots it, as will any acid.