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ianp811@yahoo.com

Hull Cleaning

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This is year 2 with a boat.  Last fall one of our neighbors kids cleaned the scum off of our boat hull.  This year it's on me.  I tried to just pressure wash it, which removes the big scummy stuff (see the right side of the attached pic).  What remains appears to be ingrained.  It doesn't removed with harder pressure washing or scrubbing.  I have not used toilet bowl cleaner or muri this year, but tried last year with not luck.  Any other ideas????   

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Starbrite instant hull cleaner knocks that right out. If its still barely there after that i would think rubbing compound and a good buff would finish the job.

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On/Off Hull Cleaner.  Been using it for 10 years and it works with very little to no elbow grease.  Just wear rubber gloves because it will burn your skin.

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19 hours ago, ianp811@yahoo.com said:

I have not used toilet bowl cleaner or muri this year, but tried last year with not luck. 

Yeah try the Starbright or On/Off like the other fellas suggested and that should work well.  Just let it sit for a few minutes when you apply it.  In your case, I would spread a first coat, let it sit for at least 5 minutes to work its way through all that crap and then put another layer right over that first one.  You'll see a lot of that stuff coming off while brushing on that 2nd layer.  Let that sit another 5-10 minutes then pressure wash it and it should clean it up really nice.  You might have to buff it out with a rubbing compound and buffer like Tuglife suggested if it still leaves a slight film.

Once you've done that, you might want to consider bottom-painting the boat.  I dealt with this crap for two years, and while I didn't wand to see my beautiful gelcoat bottom covered up, I had no choice because dealing with this is not fun and eventually will ruin the gelcoat anyway.  If you keep the boat in the water most of the season, bottom paint it.

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The Mary Kate On and Off is acid based and works very well. That said, do not get it on your trailer, or a concrete driveway and as Monkey said, rubber gloves, safety glasses, and/or face shield, and a long sleeve shirt. I use a small foam roller with extension handle to apply, and that way a quart will do at least 3 hulls. You just need to be ready and get her down as the acid will eventually begin to dissolve the plastic core of the roller.  W

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59 minutes ago, Wingnut said:

The Mary Kate On and Off is acid based and works very well. That said, do not get it on your trailer, or a concrete driveway and as Monkey said, rubber gloves, safety glasses, and/or face shield, and a long sleeve shirt. I use a small foam roller with extension handle to apply, and that way a quart will do at least 3 hulls. You just need to be ready and get her down as the acid will eventually begin to dissolve the plastic core of the roller.  W

I use a plastic paint roller tray and a soft deck brush on a pole.  Basically like painting the bottom.  I can get most of the hull this way.  Then at the end of the season I will don my glasses, gloves, etc. and crawl underneath and use a hand brush to get the areas I can't get from above.  Unfortunately, it's tough not to get any on the trailer but I keep the hose close by to continuously rinse it.  I have an aluminum trailer with galvanized cross beams.  It stains the galvanized steal.  So I have a spray can of cold galvanizing paint to retouch.

TIP:  don't get ON/OFF on the chrome logos on the boat.  It will stain the chrome.

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WARNNING !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Do not use high pressure sprayers.  Some are high enough to remove the  glassy smooth surface. As it dries. The surface WILL LOOK & FEEL like sandpaper was used.  Been there.

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Acid based work well.  it burns when you get it in yours or any open cuts you may have.  I usually try to wipe it off when i pull it out of the lake in the fall.  But you need to do it quick , before it drys on.

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I highly at least recommend a 3m respirator mask you can find at an automotive parts or paint store. The fumes can rapidly overcome you  while spraying or rolling it on. Get a excellent set of safety goggles or glasses also. Don't mess with your vision it truly is priceless. Now you can get to cleaning.

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I always have a floor standing box type fan to blow the fumes away.  Still wear a full clear face shield & gloves. With a canister type full mouth respirator.  Home Depot sells / sold all types of chemical canisters.

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Slimy Grimy has always worked well for me. Although I have also had good results with the Starbright product.

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I take a 2-pass approach.  I hit it first with a pressure washer with a 25 degree nozzle to get rid of all the big stuff, then use either the Star Brite hull cleaner, or Davis FSR  gel to get it all the way clean.

The spray-on Star Brite is faster/easier, but the Davis gel does a better job overall.

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The Davis FSR does a good job on those problem areas.  I like the spray on for it's easy application, but the wipe on/wipe off gel gets the job done better on the heavy stuff.

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16 hours ago, ianp811@yahoo.com said:

I ended up using starbrite hull cleaner and I'm happy overall but there are still some problem areas that I'll probably have to polish out.  thank you all for your help.Capture.JPG.651708d93383c8eba925cd75d9a6a1dd.JPG 

Looks much better.  Try the On-Off now with that waterline mark and some of the darker spots.  Just brush it on as thick as you can and let it sit for a few minutes so it can work its way into that crap.  You should be able to get it off then buff and polish with some compound and it'll look brand new again.

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You may want to consider painting your hull before next year as it looks like you keep it in the water. It will save you a lot of work at the end of the season.

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You all are going to laugh and be skeptical but strait lemon juice is one of the best ways to clean the algae, green scum off the hull and works like magic. Buy several bottles and use in a Hudson sprayer. Soak in and let stand for 15-20 min. Use a pressure washer on a low setting with a brush and it all comes right off. Side benefits it’s super cheap, biodegradable and smells good! 

A big marine shop here in Minneapolis told me about it and I thought he was joking. Guy bet me a case of beer my boat would look perfect with nothing more than lemon juice and I took the bet. Lost it too. 

Try it and you’ll see. 

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9 hours ago, Schnobel said:

You all are going to laugh and be skeptical but strait lemon juice is one of the best ways to clean the algae, green scum off the hull and works like magic. Buy several bottles and use in a Hudson sprayer. Soak in and let stand for 15-20 min. Use a pressure washer on a low setting with a brush and it all comes right off. Side benefits it’s super cheap, biodegradable and smells good! 

A big marine shop here in Minneapolis told me about it and I thought he was joking. Guy bet me a case of beer my boat would look perfect with nothing more than lemon juice and I took the bet. Lost it too. 

Try it and you’ll see. 

That's great, not the part about loosing a case of beer, though!  Wonder what the primary ingredient is that does the trick, or is it simply the acidity in lemon juice?  Perhaps vinegar works as well?

BTW, that's one of many, many great Abraham Lincoln quotes.  There's a reason why the Gettysburg Address is one of the most well known pieces of literature often referred to by many other leaders, from past to contemporary ones. 

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9 hours ago, Denny said:

Toilet bowl cleaner.  Denny.

+1.  Cheap and effective.

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All living fungus, mold, plants or critters. WILL DIE if they are kept covered by anything too acidic or alkaline.

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I use Iron Out toilet bowl cleaner. One cup per gallon of hot water in a garden sprayer. We're in the lake all season and will pull mid season and do a wash. Many areas don't even need to be hand scrubbed. This is the first year on a bunk trailer and the dealer did the bottom wash.... really not sure what people on bunks do to get under them..... 

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My boats bring over powered enough can handle fresh water slime. I only lose 5 mph between May 15 to September 15..   It is on the very underside. Not visable.

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On ‎10‎/‎20‎/‎2018 at 10:21 PM, watson524 said:

I use Iron Out toilet bowl cleaner. One cup per gallon of hot water in a garden sprayer. We're in the lake all season and will pull mid season and do a wash. Many areas don't even need to be hand scrubbed. This is the first year on a bunk trailer and the dealer did the bottom wash.... really not sure what people on bunks do to get under them..... 

Getting between the bunks is annoying work. 

While the boat is on the trailer, jack the boat up as far as you can go. This will not bring the boat off the trailer. After you jack it up, let the air out of the trailer tires and that lowers the trailer and creates the space between the boat and the bunkers. Wipe away. 

As for during the season. even though I put bottom treatment on the hull, I still get build up. The treatment doesn't really stop the growth as much as slows it down and is easy to wipe it off. Once Lake Erie warms up, I jump in and lightly scrub the bottom. The "stain" is still there but the scum is off. 

So at the end of the season, I need only clean the stain off. No power washing. I've used ON/OFF for 10 years.  Although I wonder if the lemon juice would eliminate the stain. I may try that next year.

As a side note, my friends boat usually doesn't get bottom treatment and they don't venture far from home. At the end of this season, the muscles layer was like a shag carpet. Awful!

On ‎9‎/‎27‎/‎2018 at 11:11 AM, cyclops2 said:

WARNNING !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Do not use high pressure sprayers.  Some are high enough to remove the  glassy smooth surface. As it dries. The surface WILL LOOK & FEEL like sandpaper was used.  Been there.

As I've posted a while ago about how weird my gelcoat is, I wonder if the previous owner pressure washed the whole boat. I've watched other boats gelcoat fade over time but mine was completely uneven and had an appearance of unusual patterns. Power washing would explain it.  

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9 minutes ago, SST said:

Getting between the bunks is annoying work. 

While the boat is on the trailer, jack the boat up as far as you can go. This will not bring the boat off the trailer. After you jack it up, let the air out of the trailer tires and that lowers the trailer and creates the space between the boat and the bunkers. Wipe away. 

As for during the season. even though I put bottom treatment on the hull, I still get build up. The treatment doesn't really stop the growth as much as slows it down and is easy to wipe it off. Once Lake Erie warms up, I jump in and lightly scrub the bottom. The "stain" is still there but the scum is off. 

So at the end of the season, I need only clean the stain off. No power washing. I've used ON/OFF for 10 years.  Although I wonder if the lemon juice would eliminate the stain. I may try that next year.

As a side note, my friends boat usually doesn't get bottom treatment and they don't venture far from home. At the end of this season, the muscles layer was like a shag carpet. Awful!

As I've posted a while ago about how weird my gelcoat is, I wonder if the previous owner pressure washed the whole boat. I've watched other boats gelcoat fade over time but mine was completely uneven and had an appearance of unusual patterns. Power washing would explain it.  

In the case of yous and mine it is just old age and exposure to the elements.  Denny

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