Barnacles on Aluminum Boat - Advice Please...

[Franko Manini]

Hey guys,

I've done a search and read a lot about removing barnacles and other marine growth off of fiberglass boats, but mine is aluminum. It seems I have overstayed my welcome at my slip and now the barnies are starting to grow. They are still small and for the most part I have been able to brush them off with my hand, at least on the side of the boat near the transom where I can reach them. I have no idea what the bottom looks like. I also noticed that the barnacles didn't grow on the side of the boat that was close to the wharf, but did grow on the side of the boat that gets more light. So I am hoping the bottom wont be too bad. I am sure they are there since my top speed has dropped from 40 MPH to 32.

Everything seemed fine and clean for the first month that I had her in the water, but then I had to go away for work and when I came back to the boat 10 days later, those little white buggers had moved in.

So, what's the drill for an aluminum hull, no bottom paint, normally trailered? Do I have to get it up on dry land and off the trailer? Powerwasher? Bleach? Other miracle chemistry? Or is this a brute force paint scraper type endeavour?

Is this an immediate concern or is pulling the boat this weekend reasonable? I must say I have been losing a little sleep over this as I have never moored a boat before.

Thanks Folks

 

[scott craven]

I would pull it and pressure wash them off.
you'll probably need to do it every 4-6 weeks

 

[ericl]

If the boat has been in the water for a month, and this "in-the-water-for-a-month" is going to be a normal utilization pattern, I'd say your boat is no longer "normally trailered. They make a specific bottom paint for AL & trailered boats. If AL compatible, some sort of hard teflon paint might be a good choice.

 

[Franko Manini]

This won't be a regular thing. I might moor it once or twice a year for short stretches, so it will remain, "normally trailered". I like the sounds of a Teflon based paint.

I am more interested, at this particular moment, in learning how other guys remove marine life, specifically barnacles, from aluminum hulls. I know it can be done using a scraper, but does pressure washing work, or are there aluminum compatible chemicals that someone can recommend?

Looks like I will be hauling her out on the weekend.

 

[trophywife]

let them dry out, soak with clr. pressure wash.. to get it perfect you may have to use a scotchbrite pad..

 

[Franko Manini]

I'll give the CLR a try for sure.

 

[gungadin]

Just so you are aware.

What surfaces should I not use CLR on?

DO not use CLR on natural stone or marble, terrazzo, colored grout, painted or metallic glazed surfaces, plastic laminates, Formica, aluminum, steam irons, leaded crystal, refinished tubs or any damaged or cracked surface. CLR may etch older sinks, tubs and tiles. CLR is corrosive. Avoid contact with wood, clothing, wallpaper and carpeting. Some laminated surfaces (counter tops) are coated with a synthetic surface which may be affected by rust removers; clean spills immediately.

http://www.thecarycompany.com/facility-supplies/cleaners/clr/faq

 

[gulfislander]

Pull the boat and pressure wash the buggers off. Works for me and my "normaly trailered" aluminum boat. In the winter you can get away with a month in the ocean. But this time of year with the warm weather 2 weeks and they start growing.
Cheers

 

[Gong Show]

Depending on thickness of growth on the bottom, a good commercial duty pressure washer will knock them off easily.
You want to do it when they are still wet, they come off easier.
My 36' commercial gillnetter had a 'naked' bottom and was in the salt chuck 24/7/365.
If the growth is thick, you must scrape then pressure wash.
As noted, finishing with scotchbrite will make it pretty.
I would not mess around with chemicals, just mechanical removal.

 

[Franko Manini]

Thanks for the pointers guys. I can see that mechanical removal is the ticket. Much appreciated!

 

[oilslick]

Hello Franco - I had the same issue and still have the same issue, I just bought the boat, pulled it out of the water as it was sitting in there for 4 months, pressure washed all the barnacles off but all the skins stayed on and they stick out approx. 2mm. I've lost 5 - 7 mph and fuel consumption is higher. I've tried sanding with a grinder and wire wheel, I've tried two different types of a acid wash, someone told me to try soda blasting but got that priced and it was going to cost me $2300 for a 19' boat, no thanks. I've also tried several hours of scraping and it does work but you really need to be careful not to put gouges in the boat and have a week worth of free time. If you find out a good solution please let me know, I've exhausted everything....

 

[scott craven]

I would definitely look at bottom painting if you're leaving in the water for that length of time.
A few weeks shouldn't be a problem as they take longer than that to develop

 

[Franko Manini]

Hello Franco - I had the same issue and still have the same issue, I just bought the boat, pulled it out of the water as it was sitting in there for 4 months, pressure washed all the barnacles off but all the skins stayed on and they stick out approx. 2mm. I've lost 5 - 7 mph and fuel consumption is higher. I've tried sanding with a grinder and wire wheel, I've tried two different types of a acid wash, someone told me to try soda blasting but got that priced and it was going to cost me $2300 for a 19' boat, no thanks. I've also tried several hours of scraping and it does work but you really need to be careful not to put gouges in the boat and have a week worth of free time. If you find out a good solution please let me know, I've exhausted everything....

Ouch. Those look pretty rough. My boat hasn't been in the water for that long, so I hope they aren't that bad. I'm pulling it out tonight to have a look. As for a solution, I will keep you posted. There is a chemical that CLAIMS to be aluminum compatible called ALGEX. Here is a link: https://www.auroramarine.com/store/algex.html. They claim the following:

ALUMINUM BOAT CLEANER SPECIALIZED IN CLEANING BOAT BOTTOMS
Algex Safely Removes Algae, Barnacles and Zebra Mussels. You can use Algex to Clean Aluminum Boats, Clean Aluminum Pontoons, Outdrives, Sterndrives, Props and Brass Rails. There is No-Fume Formula in a Ready-To-Use Spray Bottle. Our Aluminum Boat Bottom Cleaner is Fast and Easy to Use - Spray On, Brush and Rinse Marine Growth Away. It is Safe for Cleaning Sterndrives and Outboards. It won't Pit Aluminum or Strip Paint. Algex will remove Rust and Oxidation. Satisfaction Guaranteed!


WHERE TO USE ALGEX
ALGEX™ is the best aluminum boat cleaner for removing algae and other marine growth. It's safe for aluminum boat bottom cleaning, aluminum pontoon cleaning, aluminum outboard and sterndrive cleaning, aluminum and stainless steel propeller cleaningand won't turn the aluminum or stainless black or cause pin holes like other acid cleaners.


There is a video on their website that looks interesting.

 

[Fishtank]

Hello Franco - I had the same issue and still have the same issue, I just bought the boat, pulled it out of the water as it was sitting in there for 4 months, pressure washed all the barnacles off but all the skins stayed on and they stick out approx. 2mm. I've lost 5 - 7 mph and fuel consumption is higher. I've tried sanding with a grinder and wire wheel, I've tried two different types of a acid wash, someone told me to try soda blasting but got that priced and it was going to cost me $2300 for a 19' boat, no thanks. I've also tried several hours of scraping and it does work but you really need to be careful not to put gouges in the boat and have a week worth of free time. If you find out a good solution please let me know, I've exhausted everything....

That looks a lot longer than 4 months,I've kept my boat in for 4 months several times now and it doesn't look even remotely close to that. Small barnacles developed and where easily power washed off

 

[Team Tom]

One option is to maybe contact Bob Selzer 206 817-0295 to see what he might suggest. He is the states, a far tow for you, but one of the best with alloy boats. I just towed my boat four hours to have him paint my botttom.


View attachment 28077

 

[oilslick]

Thanks for the info. Honestly, my company bought this boat to do some work at the Iron Workers bridge and we used it from May and took it out of the water at the end of August and it was covered.
I keep the boat at Bridgeview Marine and never leave it in the water. I guess I will go with scrapers, wire wheels and sanding, there goes at least a weeks worth of work that cuts into my fishing time....

 

[Franko Manini]

One option is to maybe contact Bob Selzer 206 817-0295 to see what he might suggest. He is the states, a far tow for you, but one of the best with alloy boats. I just towed my boat four hours to have him paint my botttom.


View attachment 28077 View attachment 28078 View attachment 28079 View attachment 28080

She's pretty now!