Sail Drive Rubber Seal Connection

[Sunspot Baby]

Just to clarify, that outer rubber boot is not a seal. It is the upper diaphragm that keeps the sea water on the outside.

These boots have been a considerable pain in the a** for me. Last summer I replaced them both using the same process. One is glued up tight, the other is flopping around.

I have just reglued it with marine grade "Goop." Goop claims to glue just about anything together. We shall see.

George

[gulfsailor8]

Originally Posted by Sunspot Baby

Just to clarify, that outer rubber boot is not a seal. It is the upper diaphragm that keeps the sea water on the outside.

These boots have been a considerable pain in the a** for me. Last summer I replaced them both using the same process. One is glued up tight, the other is flopping around.

I have just reglued it with marine grade "Goop." Goop claims to glue just about anything together. We shall see.

George

How did the marine Goop work?

My rubber seal fell off after 3 months, Volvo doesn't have a product for this and 3M has hundreds.

Thanks,
Bob B

[svcattales]

Originally Posted by gulfsailor8

How did the marine Goop work?

My rubber seal fell off after 3 months, Volvo doesn't have a product for this and 3M has hundreds.

Thanks,
Bob B

Bob, After having the rubber boots come lose several times, I made a fiberglass backing plate and attached to hull with s/s screws and 5200. We've cruised over 1K miles since the haulout and boots are still looking good. I laminated the f'glass plates myself with epoxy. See pics:

[rja]

Originally Posted by imagine2frolic

Next year when I haulout. I am going to do this. Do you rock the drive leg back, and forth while the foam is setting up? Gideon, did you ever get my question about Boyen feathering props?

Hello. Old thread.. but I'm wondering if you ever did the foam? We're considering doing this to our saildrives since the boots constantly fall off.

Thanks,
-rja

[Captain Bill]

Originally Posted by svcattales

Bob, After having the rubber boots come lose several times, I made a fiberglass backing plate and attached to hull with s/s screws and 5200. We've cruised over 1K miles since the haulout and boots are still looking good. I laminated the f'glass plates myself with epoxy. See pics:

My boat came from the factory with a backing plate very much like these. I replaced my boots 4 years ago and sealed the backing plate with 4000 and the requisite stainless screws. The 4000 was used in the hope of keeping water from migrating down the screws and into the laminate, not as an adhesive. I decided on 4000 as it is relatively easy to remove and I'm sure that I'll have to replace the rubber boot again eventually. I had the boat out again last year and it still looked good.

[Thumbs Up]

I did the foam on both of my saildrives. My hulls are plywood and I didn't want to use any screws. Volvo's "mud flaps" are flimsy and expensive and they don't even specify an adhesive. I masked of the drive legs and hulls, injected sprayfoam, trimmed with a hacksaw blade, then coated the whole thing with 5200, then bottom paint over that. It came out a little lumpy looking but I was in a hurry and the whole thing is pretty sacrificial. Now I don't have to worry about barnacles growing in there and if my mounting diaphragm ever splits at least I have something in there to stop the water flow. The spray foam you can buy nowadays is fairly low density so I didn't think flexibility would be an issue but I do notice slightly more vibration when the engines are running but am now totally used to it and have just motored over 60 hours almost nonstop without any problems. The way I see it, the most vulnerable part of the whole saildrive system is the mounting diaphragm (you are supposed to replace it every 7 years). If you get barnacles between the hull and drive leg, the only way to remove them is by sticking something metal up in there and scraping around which could easily damage the rubber up in there. The "mud flaps" don't even create a seal, they are just to reduce turbulence and seem to fall off all the time anyway so I went with the foam and barring any unforeseen problems, I plan on doing it again each time I haulout. It is cheap, effective, and provides a safety margin in case of a diaphragm failure.