Stern Drive cleaning and painting

[DaggersJeff]

Hi guys, Bayliner 2655 owner here.
Boat currently out of water for gimbal/bellows replacement and engine overhaul. While the leg is off I am thinking about cleaning it up and painting. Whats the best way and what maerials do I need please?

 

[dpb]

Various wrong and right answers to this and it depends how bad a state it is in.
What has worked for me in the past is cleaning the leg as best you can with a non metallic scouring pad, like the green ones you get from the supermarket for washing pans. If after this you see more aluminium than paint then that is beyond my experience, but assuming just a few small patches of bare aluminium and mostly some sort of sound paint covering I do this.
Make sure all loose paint removed.
Clean bare aluminium with acetone then when dry prime with Acid#8 etch primer.
Then apply a couple of coats of Jotun Penguard HB (an epoxy primer)
Then apply a couple of coats of anti foul.

Of course if after cleaning all you see is old antifoul then I would just add another coat of antifoul to freshen it up. (make sure you use aluminium compatible antifoul)
If you are after recreating a factory fresh look, then of course the above will be of no use to you what so ever!!!

 

[BruceK]

As above. I have found that without an aluminium etch primer the leg is very susceptible to shedding any paint applied. After years of agro I completely stripped the leg down to bare metal and started from scratch. Any bare aluminium soon causes surrounding paint to lift.

 

[DaggersJeff]

Thanks for responses guys. As I dont want this to be a yearly chore, I think I will do a full scrape back while I have the leg off

 

[Tickleman]

having sterndrives on my last three boats, sorry to say it will be an annual job... Sterndrives are fantastic from a performance and manoeuvrability, but they are maintenance.

for best practice, you should pull your boat out every 6 months. Once a year to clean the intakes and around the bellows, but also (and most importantly) to check the anodes as the last thing you want is any corrosion on the drives. That being said, you can get a diver (or even yourself) to jump over the back, clean and check the conditions of the anodes.

I used Propspeed on my drives for everywhere below the cavitation plate (including the propellers and lower leg). This is meant to be renewed annually (according to the manufacturer), but i managed to pull 3 years between replacing this. As long as nothing is growing on the Propspeed areas, it's still working well.

I agreed with dpb: use a kitchen sponge scourer (like the Chux yellow sponge with the green scourer on the back) and rub over the sterndrive and until clean. I always used the scourer with running water at the same time.

I used the Jotun on my last antifoul, but I wasn't a fan. I have used Hempel brand before this and thought it worked better. However, this could be a factor of the area / water quality / temperature etc, that i'm in.

I hope that helps... Best advice with sterndrives.. use them! the more they're used, the cleaning they'll remain.

 

[BruceK]

Thanks for responses guys. As I dont want this to be a yearly chore, I think I will do a full scrape back while I have the leg off

I really went to town on mine to try curing it. etch primer, 2 pack primer and then multiple coats of 2 pack epoxy enamel that dried as hard as gelcoat. This then followed by a tie coat and AF. Total thickness about 3,5mm mostly epoxy enamel. This after spending £1300 last year to have them professionally done which still failed. The agro is immense so if you dont have to go bare metal all the way but just patch areas, I'd lean towards that making sure all aluminium was covered. I'd give an eye to know what OEM's etch primer was that enabled the paint to stick so well.