Painting the lower unit

[Manipulator]

I went to a local marina and asked about painting the lower unit. The guy there said don't waste your money (surprising from someone who owns a marina where they basically mark everything up double and try to sell you everything) as it will just come off every season. I was going to by the OMC paint and etching primer. He mentions that they have tried everything you can imagine and nothing works. Apparently they use some special procedure at the factory, possibly powdercoat?? Anyway he said to just buy some Rustoleum and paint it so I bought some white Rustoleum and did just that. Any thoughts?

 

[ryrepsak]

Re: Painting the lower unit

I just painted my outdrive with appliance epoxy. It seems it be working out just fine. I have had my boat out once so far and it has held up good.

 

[KaGee]

Re: Painting the lower unit

Oxidation is the problem. I tried to remove as much as I could, and used Zinc Chromate primer. Since I plan on eventually docking, I repainted with an antifouling spray I bought surplus on Ebay.

 

[TilliamWe]

Re: Painting the lower unit

Last winter I repainted using the cheap stuff from Walmart. The paint peeled off almost on contact with the water, but the primer (grey stuff) held all summer.<br />So, this winter:<br />I repainted by using Mercury's primer, the grey stuff. And I bought Mercury's Phantom Black paint. We'll see how it holds up this summer.<br /> <br />But if I have to repaint again this winter, oh well, so be it. Paint is cheap, lower outdrive cases are not!

 

[Manipulator]

Re: Painting the lower unit

TilliamWe, where do you boat in Illinois? I'm near St. Louis.

 

[lenny2113]

Re: Painting the lower unit

Do you guys sand the drive after primer is applied? Also, does it have to be sanded between paint coats. I plan to paint 2 coats zinc primer, 2 coats anti fouling outdrive paint.<br />Manipulator, I am sorry for jumping in here with my question. I am not a big fan of double posts.<br />Thanks.

 

[Manipulator]

Re: Painting the lower unit

No problem. I sanded mine but I just painted the whole thing with rustoleum. It probably will come off after a week. I'm in freash water and the marina said bare aluminum is no problem as long as your anodes are in good shape. It was in the water all last summer with bare aluminum and there were no problems and no corrosion. The anodes got faily eaten though.

 

[TilliamWe]

Re: Painting the lower unit

I am in Peoria. So I am pretty far away from you! I do my boating on the Illinois River.<br /><br />Lenny, I sanded the primer last year, this year I did not. <br /><br />Manipulator, I would not trust bare aluminum in my marina & on this river. My annodes get covered with growth & lose their effectiveness it seems in a hurry. Plus I have a Bravo 3, which is a whole other can of worms!

 

[Manipulator]

Re: Painting the lower unit

My anodes are pitted but still in fairly good shape. should I sand them? Would that increase their effectiveness? <br /><br />I boat at Lake Ozark. Water is fairly clean compared to the river. I have a plastic scrub brush I use on it while parked in a cove. I get my floatation pillow out, grab my brush and a beer and their ya go. Takes about a half hour to circle the boat.

 

[TilliamWe]

Re: Painting the lower unit

Not sure about sandpaper, but yeah, keep the annodes clean and they are more effective.

 

[Boomyal]

Re: Painting the lower unit

I will be painting my lower unit soon. I will sand, spray with etching primer then overcoat with a 2 part poly urethane. I'll post pictures when I do it and let you know how it holds up.

 

[Dunaruna]

Re: Painting the lower unit

The main problem with painting outdrives is making sure that the paint covers 100%. Any exposed alloy (even a pin hole in the paint) will allow the galvanic process to begin. That's why etching primer is probably the best first coat, it'll bite in. A good 2 pack epoxy will take a lot of beating - very tough stuff. Good choice boom.<br /><br />Manipulator, fresh water isn't the same from lake to lake. Different mineral content can speed up or slow down the galvanic process, your anodes are getting eaten up which is a good thing as they are protecting your bare alloy but it needs to be put into perspective. A large anode that is being eaten up quickly can be a red flag, it's telling you that there is a lot of galvanic activity. Whether or not it's a problem depends on the size of the anodes compared to the amount of material that needs protecting, and their mounted position.<br /><br />Aldo