Removing Yellow Phosphor? Stains from Gelcoat...

[MarshMarlowe196]

Seems like I remember flkeysaqua asking this question before, but it was embedded in a post about a different subject-

My boat has the yellow stain along the waterline from the saltwater interacting with the oxidized gelcoat.  Has anyone found a product that removes these stains effectively?  I don't want you guys making fun of my fishing boat during the Octoberfest

[John Jones]

Starbrite Hull Cleaner worked for me.  Not the "Sea Safe" version.  I have not tried that.

[Aswaff400]

on off hull cleaner, not the gell though, a few of our detailers use that and turn a yellow bottom looking like it just came out of the mold, use it on my boats every now and then when i really feel like cleaning it

[fitz73222]

Rust Aid from Lowes or Home Depot in a sprayer. Nocks it right off. Wet your trailer down first. On Off works great, but very causitic and you will need to visqueen the trailer or it will etch anything metal.

[Capt. Bob]

Rust Aid from Lowes or Home Depot in a sprayer. Nocks it right off.

I was going to mention Rust Aid as we get a lot of tannin staining from the rivers running into the Gulf. I wasn't sure what Bad was dealing with (phosphor)
so it might work for that too. It cleans the stains off on contact but as you stated, plays hell with the trailer.

[Glock Diver]

Rust Aid from Lowes or Home Depot in a sprayer. ...

A neighbor recommended Rust Out to me, and I picked up a bottle (white spray bottle with and orange label).  Works like a charm on the yellowish/brownish stains I had on the bottom of my hull.  Didn't even really need to scrub; I just sprayed it on before I dunked the boat, and it was nice and clean when I retrieved it.

Rust Out   probably the same ingredients as Rust Aid.

[John Jones]

If you want to go cheap, go to Lowes's ect. and pick up a gallon of Muriatic Acid.  Everything mentioned above is based on muriatic or phosporic acic.  Just dilute it about 4 parts water to one part acid.  Either cover the trailer with plastic or have a helper keeping it rinsed off the trailer.  The name brands will stain your trailer too.

*Always pour acid into water, never water into acid.

[Skoot]

SNO-Bol Toilet Bowl Cleaner hands down. Works awesome.  I tried everything else on my boat when i first got it and nothing worked.  This stuff took all the stains off and shes white as can be.

[John Jones]

Sno Bol Toilet Cleaner
Ingredient                 % By Wt.    
Water                        80-90%
Hydrochloric Acid          0-20%

http://www.imperialinc.com/msds0855230.shtml

[gran398]

Good thinking. Same stuff, different dilutions, and different prices. I'm sold on On-Off, know you guys feel its too caustic. And certainly will stain a galvanized trailer for life.  But... have you tried it for athlete's foot? (feets, feetsies, etc.)

 

[John Jones]

Yeah, it does work best because it's a combination of hydrochloric acid, phosphoric acid, and oxalic acid.  

http://www.fastenal.com/web/msds/getmsds.ex?sku=0604272

[MarshMarlowe196]

Rust Aid from Lowes or Home Depot in a sprayer. Nocks it right off.

I was going to mention Rust Aid as we get a lot of tannin staining from the rivers running into the Gulf. I wasn't sure what Bad was dealing with (phosphor)
so it might work for that too. It cleans the stains off on contact but as you stated, plays hell with the trailer.

I've been told that the phosphor in saltwater is what causes the yellow stain.  I may have been misinformed...  

If you want to go cheap, go to Lowes's ect. and pick up a gallon of Muriatic Acid.  Everything mentioned above is based on muriatic or phosporic acic.  Just dilute it about 4 parts water to one part acid.  Either cover the trailer with plastic or have a helper keeping it rinsed off the trailer.  The name brands will stain your trailer too.

*Always pour acid into water, never water into acid.

I have my boat parked in my parent's yard at the moment (much closer to the water and my dad likes to use the boat from time to time).  I showed up with a bottle of Muriatic Acid, and my Dad didn't want me to take it out of the truck.. he has a strong dislike for that stuff.  He actually suggested Toilet Bowl cleaner too, but after reading the ingredients, maybe I can just dilute it down enough to where it's not so destructive.

Question:  I have some rust stains in the boat from the anchor chain / and whatever else rusted in the boat over the past 37 years.  Will Muriatic Acid remove these stains?  After my dad put the hex on the acid, I'm afraid to use it in the interior ( I still have the original hinges on the compartments, and aside from the rod holders and the hull itself, they're the only thing original in the boat anymore ).  Is there a method to applying it that will prevent it from destroying metal?  How do you apply it?

[John Jones]

I have not tried the acid on rust on fiberglass but I would not hesitate to try it.  I use Bar Keepers Friend for minor rust stains but have never had to deal with the really bad rust stains.  Muriatic acid will NOT hurt stainless as long as you wash it off well within a reasonable amount of time.  I use some diluted muriatic on a paper towel to clean rust off of stainless (and a rubber glove of course).  I have no clue what it will do to aluminum.  I have a piece of polished aluminum 1" tubing.  Maybe I will put some on it tomorrow and see what happens.

[Mike453]

John, muriatic acid will eat aluminum , On small engines we used to use acid to remove connecting rod material (aluminum) from crankshafts, we bought it at any hardware store,20% I believe.

[John Jones]

I was afraid of that.  

Waayy back in high school my buddy's grand dad gave him an old Renault that smoked like a mosquito fogger.  We tore the motor down with intentions of rebuilding.  He soaked the rods and pistons in a strong Drano solution for a couple of days (cause that was the only strong cleaner we could find around the house).  There were no rods or pistons left in the vat.  Just the rings.  Moral of the story is a caustic solution will eat aluminum as well.