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Antifoulant for outboards?

D

dvgibson

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I have a Honda 9.9 on my sail boat, it is in a well and cannot be pulled from the water when not being used. I've tried the spray coatings to no avail. The engine looks like a kelp forest after a couple of months. And what concerns me more, the limpets and tiny mussels that grow on it, blocking the vents. No one around here (southern Maine) seems to have any suggestions. Has anyone found something that will at least help?
 
I've often wondered about how people deal with the in-well outboard fouling issues. You would think, that by now, someone would have invented a "lift" system for sliding the motor up vertically to help with the growth problem. But, I suppose, that would defeat the "out of sight" feature of the well.

Good old ugly bottom paint and plenty of movement is all I know of that keeps the critters off... but it doesn't do a thing to keep them out of the submerged water passages.
 
Can you really use bottom paint on the outboard? I know the antifoulant for aluminum boats is different from those with fiberglass. Or wood.

You would not believe how hard it is to get this 117 monster in and out of the well. To start with it is below your feet! When the boat is on the hard for the winter I have a crane rigged in a nearby tree. I have used an a-frame when on the water attached to the back stay. And block and tackle of course.
 
DO NOT USE regular antifouling paint on an outboard! I use a water based ablative anti fouling paint on my sterndrive. While its available in a spray, I buy the same version in a one quart can. It costs more in the can, but the can will last you several seasons. It is also easier to control the coat with a brush. I just got 3 seasons from one can on my sterndrive... it's way bigger than your O/B. The one I use is...Aluma-Coat by Flexdel.
(no connection, just a satisfied customer)...

http://www.aquagardboatpaint.com/productlines_detail.php?cat=Alumi-Koat%20Brushable

While anti fouling paint is usually sold as one size (formula) fits all, different formulas work better in different waters. Give the folks at Flexdel a call. They were very helpful when I called.
 
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Thanks, Capt Bob, I will look at Flexdel. I also just read that Interlux 33 is recommended for aluminum boats, outdrives and outboards. Might find that at the local marine store. Only seven days to launch.
 
A couple of my neighbors and I leave our boats in the water year round here in the FL Keys. We have tried the coatings "designed" for outboards and none of them last down here. What works is regular bottom paint. You don’t want to put it on bare aluminum, but with good paint under it there does not appear to be any harm to the aluminum at all.

BTW, I looked at the aquaguard link posted and they list cuprous oxide as their active ingredient. That is the same active ingredient in bottom paint so it’s probably why the poster has such good luck with it ;)

Tom
 
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