How to clean boat's bottom to end the season?

[yogi799]

This year for the first time, my boat spent the entire season in the water (great lakes, fresh water). Naturally the bottom is dirty AF.

I understand i will have to clean it but my question is for ending the season and pulling the boat out of the water. How do i clean the area where the bunks will hug the fibereglass??? Will it need to stay dirty forever, since i can no longer clean it when it sits on the trailer. Or do people dive under the boat (I do a lot for fun) and somehow "pre-clean" the bunk slide area before pulling the boat out???? No clue. lemme know pls.

 

[Denny]

How big is she, and fresh or saltwater?

 

[yogi799]

24 ft, fresh water as stated.

 

[Denny]

Sorry about that, (old eyes).
I can only tell you what works for me to expose my total bottom.The very back of my keel is flat and is not rounded or V pointed. They called it a planning plate. So I get a large thick block of wood and a floor jack and raise it from there with it still attached to bow winch. I'm on an EZ-Loader trailer. What might be able to do is lift one side at a time an hit it with a pressure washer. Another way is a long pole with a brush on it. Do you go to the beach with it? Which of the Great Lakes do you boat?

 

[Iwantachaparral]

Captain Phab. Algae and rust remover with some hot water. Brush on and let it work. Rinse it off. Repeat if necessary. I just do the best I can with a long reach brush and work around the bunks. I hate I can’t get under them but it is what it is.

 

[yogi799]

I'm on Georgian bay and yes I'm frequently near the beach or shallow rock so I can reach. But wasn't sure how cleaning under water is possible. Lifting the boat sounds interesting but mine is 5k lbs so quite risky probably.

Iwant leaves bunks locations dirty. Ok I understand. That's probably what I'll do too....

 

[Iggy]

I know what you guys are going to say. NO!!

But I have found that bottom paint works the best. Keep in mind that bottom paint will seal the glass from water intrusion too. You might loose 1 or 2 knots at WOT. But it beats cleaning the bottom after being left in for more than a week depending on location.

After leaving my boat in all season, just a light presser washing to clean it.

 

[yogi799]

Really? Dirty marina water doesn't stick to the paint? Also what paint?

 

[Iggy]

Bottom paint is what its called. As in one example: https://www.westmarine.com/bottom-paint/

Many brands, colors and types.

 

[yogi799]

OK, thanks, I will do some reading about it... Question remains what to do about the bunks. No way to paint the bottom in the water or out of it....

 

[Iggy]

I had rollers, so I could easily move the boat 3 to 4 inches. Personally, I did not like the bunks. They made it harder to launch or recover my boat. But rollers need to be maintained.

You could use boat stands too. I can explain that if needed.

 

[yogi799]

Oh I see. OK, and i wonder if bunks will rip the paint off too more easily. Lots of research to do. I love bunks personally but have never kept the boat in the water all 3 months so this is new area to me.

 

[Doc]

Slimy Grimy is a product I've used to clean the bottom after an extended stay in the water. Works great. Strong stuff.

 

[SST]

My boat sits on bunks. The previous owner clearly didn’t treat or clean the boat where it sat on the bunks. The way my trailer is designed, I cannot remove the boat and put it on stands. The only way to get at these areas is to raise the boat and then lower the trailer. I learned this from a former poster from the previous forum. It’s a pain but it works.

The first thing I do is jack the boat up. With my trailer suspension, it will not raise the boat off the trailer. To create the separation, I have to let all the air out of the tires which lowers the trailer and hence you can clean and treat the entire bottom. When your done; put air back into the tires and then lower the boat.

In regards to bottom treatment you can do either as mentioned above. Depends on your attitude towards doing it yourself and save some money or have someone else do it. I do it myself.

This season I had to switch to a product called 721. It’s a thick paste. I was really skeptical at how well this would work. It requires 2 coatings over two days. 24 hours to cure for each coating. I was a bit cranky about it but I went ahead and applied. This stuff is amazing. In summary, it doesn’t really prevent growth but if you take the boat for a good ride it all comes off. I have been keeping a keen eye on this all summer.

The sunny side at the water line seems to be susceptible to growth. When I first saw this at the beginning of the season I was mad thinking, “Already!? “ When I jumped into the lake with a scrub brush in hand, when I got underneath the hull expecting to scrub the whole thing, clean. Not absolutely pristine clean but so clean I climbed back in the boat as a happy camper. It’s been like this all summer. Take it for a ride and it all comes off. Even the outdrive remains clean and that takes direct sunlight.

It’s going to be interesting when I check my boat tomorrow (Sunday). I’ve been out of town since last week so lots of sun and no movement. I’ll let you know. Hope this helps.

 

[SST]

As for cleaning the bottom at the end of the season, I give it an acid bath the same way I put treatment on it. Raise and lower the boat and trailer. I take a paint pad and apply it. This minimizes drip. Then flush it like hell including the trailer.

 

[Iggy]

Paint the boat the best way you can. The next time you go out, position the boat differently. Then go over the spots you missed.

 

[Denny]

I have an E-Z Loader with rollers and I have always trailered. Back in the late 60's I had a 15 ft Mark Twain with bunks, that I also trailered. So with bottom paint, I never had to wash the bottom. My question is, what if you did not put the trailer in as deep as you normally do to retrieve your girl, and you had the use of the ramp without holding anyone up, could you retrieve and launch, say 2 or 3 times, and would that give you the friction needed to clean the areas where your girl would set when fully retrieved?

 

[SST]

Here is my boat with a partially complete acid bath. The 721 bottom treatment did a good job of protecting my hull. No extreme slime or zebra muscles. The bath is easy to do, it just takes time.