Lower unit coating

g0tagrip

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A couple years ago we trashed my starboard engine lower unit, we hit something, anyway I bought a lower unit from SEI over in Tampa. after a couple trips the coating started to peel off. I sanded and painted but it just kept peeling off. Finally took it off and now I am going lot stripe all of the coating off, sand it down, prime and paint it. My question is has anyone had to do this and if so what paint did you use. The spray can paint is a lousy option, I want a thicker two part paint. Recommendations?
 

DennisG01

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Neither, the coating is a thick almost plastic and thick and hard.
There is no thick, plastic coating used on lower units - it's either paint or antifouling (which is also paint). I think you'll have to better explain or, ideally, post a couple of pics so we have a better idea of what you have there as it sounds like something out of the ordinary.
 

wspitler

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If you are sanding down to bare aluminum, you will want to use a chromate conversion coating such as Alumaprep or Allodine. Follow the directions for either. I seem to remember that one of those is not suitable for cast aluminum. You can do the research on that. Next I would use a zinc chromate primer followed by a good enamel or two part polyurethane.
 

seasick

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A buddy of mine installed a new Alpha one SEI unit about 10 years ago. The instruction that came with it had explicit steps for priming and painting the housing. My buddy decided he didn't need to do all that work and just pianted the unit with engine paint. After about 1 year of service, the unit basically ate itself up.
I suggest that you call SEI and ask what the recommended treatment is.
 

D.D.

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I suggest that you call SEI and ask what the recommended treatment is.

^^^^This.......
 

g0tagrip

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Ok, thanks. I will give them a try, but my experience with SEI is not good. When the coating stared to peel off I sent the unit back two them under the warranty, at great cost to me, and they did nothing and sent it back to me, without any repair to the paint.
 

seasick

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Sorry to hear that. In the past they have been responsive.