Sterndrive electrolysis and antifouling

[joliette]

I'd like to antifoul my Alpha sterndrives which are fitted with stainless props and protected by the Mercathode system. Mercruiser recommend leaving a 1" gap between the hull antifouling and the gimbal. I assume this is to prevent electrolysis between copper based hull antifouling and the gimbal and drive. So, what is best practice? Use a copper based antifouling on the hull, leave the 1" gap and apply a sterndrive antifouling to the gimbal and drive? Or, apply sterndrive antifouling right across the transom?

The drives are going to be used in a high fouling area and the boat will be kept afloat for extended periods, so it is not going to be realistic to leave them untreated.

 

[carlton]

I'm into my second year of using EU45 in white. I mention white because it's the only one they do which can be used on both the hull and drives.

Pretty impressive so far. You do get some growth but it just falls off as soon as the boat starts moving.

I also coat my SS props in Lanoguard which is more effective (and considerably less expensive) than any other treatment I've found.

 

[jhr]

I leave a gap between the transom and outdrive. I guess there's no reason why you couldn't paint the entire transom with sterndrive antifoul, except that it would be effin' expensive. Also, from an aesthetic perspective, I doubt you'd get a colour match between the sterndrive paint and the antifouling so it might look a bit odd. Probably acceptable on a bog standard production job like my boat, but on a classic like yours..... (I assume we're talking about your Settimo Velo here?)

 

[Greg2]

I always left a 1" gap around the transom shields. No real problem with fouling. Did teh drives themselves with Trilux.

 

[KevB]

Yes, a gap between the transom and the sheild. Use paint on leg paint rather than the spray on stuff cause it works MUCH better. And the proof is I sprayed the transom sheilds and painted the rest of the legs. Given that the sheilds are tucked up out of the way of sunlight they are much worse than the legs.

 

[joliette]

Yes, this is for the Settimo Velo ... The EU45 would be fine if it was in black, but I may give that a try on the hull as it looks to be a very reasonable price. I've used Trilux before and found that to be a good product so I may give that a try on the drives and gimbal. However, I'm now wondering if it's possible to buy anything in an aerosole as that could be handy for painting the gimbal ...

 

[KevB]

. However, I'm now wondering if it's possible to buy anything in an aerosole as that could be handy for painting the gimbal ...

See above

 

[ian38_39]

we have used seajet emperor 034 for the last five years, paint the whole lot (hull and drive) with the same thing, yes the drives are navy blue but they dont get fouled.

 

[oldgit]

Vital in salt water,to get a good thick coat of Tri lux on ALL of the outdrive.The difficulty of getting the A/F up under and inside all the nooks and crannies of the outdrive transom shield and bits is why the job does not get done properly half the time.Applying by brush may not look very pretty but its not visable anyway and you can get a decent thickness of paint over everthing,including you.
Personally think it looks best in white or grey,although have used garish bright blue when 5 litres came up cheap on Ebay recently.
Whatever hull anti foul was used I always left 25mm or so gap around leg depending on width of masking tape being used.
As you are know doubt aware A/F needs to be done more far frequently in salt whereas in fresh it can be several years before a recoat is required.

 

[rule the waves]

Copper

I too leave a gap between the hull antifouling and the drive's. It's a volvo drive, and they strictly recommend not to use any other than prop antifouling. Which I do...But, on the other hand, a free "cheap trick": I mix very fine copperpowder (to obtain through the internet) in my hard antifouling. About 2 small cups in 2,5 ltr. paint. Once mixed very well, the powder becomes invisible and does an incredible job. Only issue (for some) is that, after some time in the water, the hull gets a light green shine. I however, don't mind at all. And the fact is: it's bloody cheap compared to some commercial stuff on the market !