My boat is in the water May through September, so it picks up some lake snot. What do you guys like for cleaning that off before it goes in the shed for the winter? I have a power washer and I've used vinegar with a scouring pad in the past, but I'm thinking there must be something better. It's a 17' fiberglass hull.

Immediately after removing from the water, powerwash it. Then spray bleach from a garden sprayer, and powerwash again. Best to let the bleach soak for 15 minutes or so, before washing again.

My wife found toilet bowl cleaner does an excellent job of getting the scum off.

A good pressure washer goes a long way. Something at least 2500psi, especially with fiberglass. Wood, you may want to go with a little less pressure, same if you're using it on a carpet. One with the interchangeable nozzles are better, the little "fan" nozzle has worked for us pretty well, there's another that rotates, that one works well too.

I know there's some good electric pressure washers, but I prefer gas power. The pressure at the supply line helps if there's a good supply.

Cleaning up the hull, do it as soon as you pull it out of the water! If the alge & gunk dry up, it's a royal pain in the butt to clean off. We use "Simple Green", either the regular or the heavy duty, in. A 5ga bucket and toss in the detergent line for the washer. Get one of those hand sprayers, and hit the hull with simple green and let it soak for a few minutes before you pressure wash it. Occasionally you got to hit a few spots with a stiff bristle brush.

Depending on how bad it is, one is washing one side of the boat, someone else is keeping the other side wet with a garden hose.

Boat wax/hull wax helps a lot! Give it about a day or two after its washed, and wax the hell out of the hull, another light coat before you toss it in the water at the beginning of the season.


Beer helps, whiskey/bourbon too, a good radio in the background... It's a lot of mindless work that requires elbow grease.

Definitely pressure wash ASAP once out of water.

I've had great results with Lime Away... the gel. Apply with a microfiber or soft brush to a thoroughly wet fiberglass hull from the keel to bond line. Rinse each section as you do it. Then rinse the piss out of anywhere it may have gotten trapped, like stainless or aluminum rub rails and fittings. Its pretty mild but will tarnish certain metals and metal finishes.

Used carefully, it really cuts the elbow grease way down in my experience.


If Severe, Muriatic acid (pool acid) keep in mind the extreme corrosion potential to your boat, engines, outdrives and the trailer.... anything else in the path of its fumes.

IME a pressure washer primary served to damage the artwork above the water line before it started to remove an appreciable amount of scum.

Thanks guys

Pressure washes aimed at the edge of vinyl graphics or Reg. #'s will certainly strip them off. Just avoid them or let the fan of high pressure water glide off the edge so that you're not forcing water under the decal.

One of Queen Victoria's favorite stories (hearsay, no references) occurred at a dinner where the person sitting next to her was a hearing- impaired admiral. He was talking about his flagship when someone asked him about his wife.

He replied, "Fine. When I get home I'm going to pull her out of the water, roll her over, and scrape the barnacles off of her bottom.

Muriatic acid for a minute or two then a thorough rinse. Do not breath that stuff. Use something like a weed sprayer to apply on a calm day.

We have the exact same usage pattern and issue, even on a relatively clean lake.

Found this product a couple years ago and two applications had the 15 year old hull almost like-new white again. Since then one go works each year.

Just put in spray bottle, spritz it everywhere below waterline, let it rest 5-10 minutes and rinse well. For stubborn spots can use a mop or similar scrubber. If you have algae or the like cleaning with high pressure first makes sense, this is more for discoloration.

Hull Cleaner

Rust Aid. Period.

Speaking from 20 yrs experience with a 42’ aluminum boat and 17’ Whaler kept in the water all summer.

quote:

Originally posted by bcereuss:
Rust Aid. Period.

Speaking from 20 yrs experience with a 42’ aluminum boat and 17’ Whaler kept in the water all summer.

Which one? The Goof off?

quote:

Originally posted by Georgeair:
We have the exact same usage pattern and issue, even on a relatively clean lake.

Found this product a couple years ago and two applications had the 15 year old hull almost like-new white again. Since then one go works each year.

Just put in spray bottle, spritz it everywhere below waterline, let it rest 5-10 minutes and rinse well. For stubborn spots can use a mop or similar scrubber. If you have algae or the like cleaning with high pressure first makes sense, this is more for discoloration.

Hull Cleaner

This is the stuff to use. There is also a product called FSR (fiberglass stain remover) that’s the same thing but in gel form. It’s great for when your under the boat so you risk getting it in your eyes

Both will strip all wax though, so be sure to thoroughly rinse amd wax afterwards. You can usually pick the starbrite hull cleaner up at any Walmart

I thot you were talkin bout Monkey Butt. There's a cure for that too, but don't go on the boat till it is.

quote:

Originally posted by ensigmatic:
My wife found toilet bowl cleaner does an excellent job of getting the scum off.

Power wash then TB Cleaner and scrubber if necessary. Use rubber gloves as the TB cleaner will burn skin. We use the gel type as it tends not to run.

quote:

Originally posted by Pyker:

quote:

Originally posted by bcereuss:
Rust Aid. Period.

Speaking from 20 yrs experience with a 42’ aluminum boat and 17’ Whaler kept in the water all summer.

Which one? The Goof off?

The version I use has a UPC OF 93945-00101 and comes in a brown jug. Not sure if it can be bought anymore. I bought a bunch years ago when I sensed it may be discontinued.

quote:

Originally posted by bcereuss:


The version I use has a UPC OF 93945-00101 and comes in a brown jug. Not sure if it can be bought anymore. I bought a bunch years ago when I sensed it may be discontinued.

That's a shame

Don’t have much to say about cleaning the bottom that the others haven’t said but make sure you keep the sacrificial anodes replaced to save the outdrive. I learned it the hard way as corrosion ate up the inside of the outdrive where the paint was worn off.