How to Remove Yellowing water lines from the Hull?

[McIntoshUSA]

When we bought our boat it had some yellowing color on the Hull. (See attached Photo) The previous owner said it was from the salt water. I have tried to remove it with wax, toilet bowl cleaner, soft scrub, polishing compound, and simply green. I do believe it is a little better than it was but still cannot seem to get it all off. Any suggestions as to what might remove the yellowing tint? You can see the discoloration right above the red water line.

Thank You, Mike

 

[Bill Murray]

Try this - worked wonders for me and friends....

http://www.acehardware.com/product/index.jsp?productId=3607507

 

[Maine Sail]

You need a good acid. I tend to prefer On/Off GEL as it tends to stay where you put it and not on the bottom paint to eat the copper. One bottle will last you ten years....

Removing Tannin Staining

 

[Stu Jackson]

FSR, also a gel.

We call it the bow mustache.

 

[Hydro Therapy]

That will work. Just make sure you don't get it on the bottom paint. I would tape off the bordering area between the gel coat and bottom paint. Pour some of the acid on a towel and rub the soiled area. Once removed hose off the hull. The water will dilute and neutralize the acid.

I've used the same product but in a gel form. It works great because it doesn't run. I picked it up at West Marine, it's called, " On Off".

 

[LakeOntario270]

Starbright Hull Cleaner - basically same thing as acid.

 

[Jake N Eggs]

Iron out works like magic. Mix some powder with water in a garden sprayer and spray it on. The stain will disappear before your eyes.

http://www.superironout.com/

 

[Hayden Watson]

I will second the FSR (Fiberglass Stain Remover). It is a blue jell and does a great job of removing stains from jelcoat. for years I had a very bad rust stain in my cockpit from a single edge razor blade that was left out for several weeks. I applied the FSR and let it sit for about 30 minutes and the stain was gone. I found it at my local Ace Hardware.

 

[redhead78]

Marykate hull cleaner, use gloves, and eye protection.it will hurt your skin. It has oxalic acid in it, and it takes off those yellowish brown stains right off. Red

 

[Anonymous 121765]

You guys may find this funny but, 15 years ago a yard worker told me what to use.

We had a tanker run aground years ago & it sent top water oil up into Tampa Bay, right where my boat was docked. On a bottom job haulout I used this:

Now don't laugh but it was:

"Sno Bowl Toilet Cleaner." You can pick this up anywhere. It brought my yellowed oil stained hull bright white. It is an acid so, you want to wear chemical gloves. The acid neutralizes when it hits water so, no environmental impact. And, it didn't effect my newly painted boot stripe.

Don't leave on too long, a fine scrubby pad or sponge will work just fine. Don't let it sit on your boot stripe too long either. Hose off as you go. It's an easy clean.

And, the price is right. Also, no matter what acid you use, it will need to be wax-sealed.

CR

 

[Charlie Jones s/v Tehani]

All of the items mentioned are based on Oxalic Acid. Oxalic acid in crystal form is available at ACE Hardware, and many other places, as Savogran Wood Bleach. Dilute it in water, and do the same thing, except MUCH cheaper.

Folks who do the ICW call that stain "the waterway frown". The Oxalic acid will wipe it right off, even using salt water to dilute. Quite a few Waterway cruisers carry it aboard all the time.

Edited to add. My boat has a hull painted with a 2 part polyurethane. Works fine on that in addition to gel coat.

 

[McIntoshUSA]

Thank You everyone. I got some of the On/Off. It worked great after a few hours of applying it to the whole boat above the water line. Now the boat finally looks white.

Now that it is clean should I wax the hull (above the water line) or should it be left alone? If I should wax it what is the best wax to use?

Thanks

 

[Tom G P-21]

Please check your MSD on what you are using first. On Off's active ingredient is Hydrochloric Acid, nasty stuff, thats why you need to use gloves eye guards and mask off everything else. It will pit your galvanized trailer. Some of the other stuff like sno bowl cleaner, Bar Keepers friend is oxalic acid and is a little more user friendly. I would try an oxalic based one first and if it is really stubborn go for the hydrochloric based stuff.

 

[Benny17441]

You can use ON OFF Gel and I would use a hand applicator with wet sand paper of 1000 or 2000 grade to reduce the need for elbow grease.

 

[njlarry]

We boat in Cedar water, hightannen, spray nine works almost as well as on off but is much less toxic and more convenient.

 

[spraygun]

 

[woodster]

You need a good acid. I tend to prefer On/Off GEL as it tends to stay where you put it and not on the bottom paint to eat the copper. One bottle will last you ten years....

Removing Tannin Staining

this stuff works as good a spotless stainless and just as easy paint in on let it set and rinse it off doesn't get any easier than that

 

[Stu Jackson]

Thank You everyone. I got some of the On/Off. It worked great after a few hours of applying it to the whole boat above the water line. Now the boat finally looks white.

Now that it is clean should I wax the hull (above the water line) or should it be left alone? If I should wax it what is the best wax to use?

Thanks

Uhm, if you read the posts, you'll find the answer. :cry:

 

[Joe Blizzard]

Oxalic acid in crystal form is available at ACE Hardware, and many other places, as Savogran Wood Bleach. Dilute it in water, and do the same thing, except MUCH cheaper.

It doesn't take much of this stuff. I use a tablespoon or so of the Savogran crystals in a quart spray bottle. I like to add some Dawn dishwashing detergent to make it stick to vertical surfaces better so I don't have to reapply. (Without the soap it sometimes runs off before it finishes removing the stain.) It doesn't seem to affect my VC17 bottom paint or my trailer's paint at this concentration. It does give off some fumes, a snootful of which can be unpleasant.

 

[wflowe2]

I had good results using Auroras Waterline Stain Remover. I'm sure it is acid based but I applied it with a small paint roller using just enough to cover the stain and not run down on the bottom paint. Just let it sit a minute or two and hosed it off. No scrubbing at all and the waterline looks new.