Cleaning a super super dirty boat

HortonHorton Posts: 25,801 Administrator
What is the secret stuff to get stains from nasty water out of white gel coat? I saw some college kids today with a green & brown boat that should be green & white.

Seems like I have heard of guys using toilet bowl cleaner. Is that right? Is there a specific product?

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  • h2onhkh2onhk Posts: 246 Baller
    edited February 2018
    Toilet bowl cleaner works good. The higher concentrate of hydrochloric acid the better it will cut hard water build up. I use The Works or Sno-bol. Just keep it away from decals and rinse the trailer and concrete floor with water when done. It will cause rust on a trailer and can cause weak concrete to pop sometimes.

    Also remember that the acid will cut any and all wax that's on the boat. Several coats are recommended after cleaning otherwise the brown stain will come back quickly.
  • MISkierMISkier Posts: 2,273 Mega Baller
    StarBrite Instant Hull Cleaner.
    The worst slalom equipment I own is between my ears.
  • ScottScottScottScott Posts: 598 Crazy Baller
    I've even gotten the attwood hull cleaner from walmart, works pretty good.
  • Jody_SealJody_Seal Posts: 2,434 Mega Baller
    Pressure washer. A light scrubbing with final glaze then wax on wax off x2.
    Hobby Boats can be expensive when the hobbyist is limited on their own skill and expertise.

  • NandoNando Posts: 439 Crazy Baller
    Second the StarBrite- it will deal with the nastiest hull stains.
  • eleeskieleeski Posts: 3,655 MM Trick Skier / Eccentric Person
    Pool acid gets rid of stains from leaving your boat in the hard water for multiple years. Brutal stuff. Burns your skin, nose and lungs. Even if you are careful. Destroys sprayers so a water bottle with a hole drilled in the lid is a simple enough applicator to work. Outrageous stains call for desperate measures.

    I'm so glad my boat is indoors on a lift. Never need to clean the bottom with acid now.

    That UCLA boat is bad but nowhere needing the pool acid treatment. Milder acids or just elbow grease should work for them. Fixing the small manifold leak is more important.

  • DanoDano Posts: 107 Baller
    edited February 2018
    The safest and likely most effective is to use a good cut polish. Use a wool pad and a high speed polisher, once the staining is gone switch to a foam pad and buff to high gloss shine. Mist your buffing pads with water during this process to keep them damp. Essentially its like sanding off the stain. Make sure you keep the polisher moving so as not to "burn" through your color. Although Gel coat will not burn through very quickly. The wool pad will cut through and remove the stain very quickly but will likely not leave you with a glossy finish. The foam pad will restore the shine very quickly. Its a simple process but if you have not done it before it might be best to bring in some help. Choice of polish makes a huge difference. when your done the boat should look like its fresh off the showroom floor. Now wax it!
  • pcmcon729pcmcon729 Posts: 38 Baller
    My boat has never been anywhere near as bad as the neglected boat mentioned. But, I would likely use a power washer to remove the heavy stuff, then use, "Mary-Kate On and Off Hull and Bottom Cleaner". Wicked strong stuff. Active ingredients are : Hydrogen chloride, Phosphoric acid, Oxalic acid. Must wear respirator, long rubber gloves, and long sleeved shirt. After clean, use 2 coats of good quality PASTE wax to help prevent that sort of staining again. Dirt is generally afraid of my boat.
    Than_BoganPat MMick04
  • oldjeepoldjeep Posts: 3,142 Mega Baller
    Set it in the water for a while then use a blue scrubby sponge on it first. Always amazing how much of that stuff comes off without anything more than a good soak. Then I'd go with a cutting compound.
    Chuck P
    Not a mechanic but I play one at home
  • MISkierMISkier Posts: 2,273 Mega Baller
    edited February 2018
    Try the StarBrite first. You should be able to get it at Walmart. They even have a spray gel version to cling to the hull better. It should not take any more effort than to spray/wipe it on, wait for it to work, and rinse/wipe off. If it doesn't work, then do all that scrubbing, buffing, compounding, or application of other noxious chemicals requiring a hazmat suit.
    The worst slalom equipment I own is between my ears.
  • JordanJordan Posts: 1,027 ★★★Triple Panda Award Recipient ★★★
    another vote for the Starbrite Hull Cleaner. It works much better than the toilet bowl cleaner/hydrogen peroxide concoctions.
  • jayskijayski Posts: 632 Crazy Baller
    @Horton Lysol toilet bowl cleaner, (just regular one, no flavors) works amazing, pressure wash what you can off, apply cleaner let sit for 10min ish and pressure wash off. No scrubbing....Former Nautique dealer actually recommended it
  • LeonLLeonL Posts: 2,259 Crazy Baller
    Go the chemical route. Use rubber gloves and DO NOT spray, squirt or other wise make it airborne. Then you have to breath it. It's bad enough to breath just from wiping. Pour on a cloth and wipe on generously. Let stand until stain goes away and rinse thoroughly. Apply good wax before putting boat back in the water.
    Leon Leonard Stillwater Lake KY - SR Driver SR Judge
  • jhughesjhughes Posts: 803 Mega Baller
    The big concept here, regardless of what particular acid-based product is used, is that the product is eating organic/mineral matter out of the pores of the plastic. This is not an elbow-grease ordeal, it's spray on and watch the stain disappear. For me, 50/50 cut muriatic acid and water in a sprayer worked great.

    I'll echo warnings here about not breathing it in and that any of this stuff will absolutely destroy your trailer with corrosion, particularly the Ram-Lin style trailers where the bunks are tapped right into the main structural members of the trailer.
  • HortonHorton Posts: 25,801 Administrator
    You guys are awesome. College kid asked me what to do you last night I said I don't know I'll just put a post in the Forum. Now he can read it and figure it out

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  • 6balls6balls Posts: 4,893 ★★★Triple Panda Award Recipient ★★★
    Star brite...easy purchase, easy to use, put it on with a sponge and you don't even scrub. The areas you touched magically whiten up behind you as you go, work in sections so as to rinse before it dries on powdery.
    Dave Ross--die cancer die
  • CCRSKRCCRSKR Posts: 3 Baller
    Davis FSR (Fiberglass Stain Remover). It is a blue gel that you can put on the any surface (horizontal-vertical) and it will hold. Leave on for a few minutes and rinse. Amazing results. Amazon and most of the online boat supplies stores carry it.
  • JordanJordan Posts: 1,027 ★★★Triple Panda Award Recipient ★★★
    Whatever you use, rinse with tons of water. You want dilute the acid as much as possible before it hits the ground.
  • dhofertdhofert Posts: 212 Baller
    We just started using some glaze today we had laying around the shop. Cuts through pretty good. Hope to finish next weekend and get some wax on. Then sit back and wait for the water to get wet again.
  • buskibuski Posts: 110 Baller
    HC-1 hull cleaner, found it through the forum, developed by a skier if I remember, worked great.
  • Bill22Bill22 Posts: 1,460 Crazy Baller
    +3 for Starbrite as listed above us a sponge or cheap paintbrush to put it on. The bottle says to use a spray bottle but you don't want that acid flying around in the wind.

    I tried toilet bowl cleaner, for me it did not do much on stains.
    In gear. Hit It. Thank You!
  • DeanoskiDeanoski Posts: 747 Crazy Baller
    Clorox Toilet bowl cleaner the type with no peroxide 4 dollars for two bottles get it at any grocery store.

    sponge on dry hose off cheap and easy. stubborn area's repeat

    make sure to use gloves or it will burn your hands!

  • sethbakescakesethbakescake Posts: 2 Baller
    Thanks for posting this Horton! And thanks for all the suggestions everyone!
  • Chef23Chef23 Posts: 5,657 Mega Baller
    Our boats are super dirty every year when we pull them out of the water as they sit in the water from mid-April until late October. One of the acid wash products cleans them up very easily but they are very caustic. The HC-1 Hull Cleaner works very well also. It requires some gentle rubbing but is much less nasty than the acid products.
    Mark Shaffer
  • BraceMakerBraceMaker Posts: 2,904 Mega Baller
    When I worked at a Marina we skipped the up charge and purchased Muriatic Acid by the gallon. All the toilet cleaners have cut back on acid content and have stuff you don't need. And hull cleaners tend to have the boat mark up applied. We had a lot of boats that sat in brackish water all season and often didn't get the offseason tune up.

    Step 1 - pressure wash and scrub with brush to remove any crusts/accumulation.
    Step 2 - Start somewhere hidden prepare 2 gallon of water in a 5 gallon bucket and add some Muriatic acid (same HCl Acid as in toilet bowl cleaner). Apply and see if its effective, add a bit more acid at a time till reaching a strength that is cutting the color. Work in sections, rinsing completely.

    Step 3 - full soap and water wash down.
    Step 4 - buff/polish
    Step 5 - Wash + Wax.
  • Mick04Mick04 Posts: 29 Baller
    Really tough stains, ON/OFF. Downside, it is hard on lungs and trailer. Another option is Captain John’s Boat Brite, which is supposed to be an enzyme, not an acid. Easier on lungs, trailer and environment, but may need two applications for really tough stains. West Marine carries it now.
  • ski6jonesski6jones Posts: 820 Crazy Baller
    Do the acid based solutions damage galvanized steel also?
    Carl Addington, Lakes of Katy, Texas
  • ShererSkierShererSkier Posts: 117 Baller
    I used JJVs Best boat cleaner. Worked great on decent scum line. Acid free, so no worries about harmful effects. Spray on, let sit and spray off. No scrubbing. If your looking to make it shine after, (like someone said earlier) rotary buffer with wool pad and cutting compound. Then foam pad polish, and I use orbital buffer for applying and removing wax. Boat still looks really great for being a 86!
  • ALPJrALPJr Posts: 1,635 Crazy Baller
    @ShererSkier pic's of the 86?
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