Saildrive or shaft?

[Skylark]

Anecdotally I have heard of baby mussels lodging themselves in the cooling intake of a sail drive........

I was concerned that this may be a problem so at 5 years I wrapped clingfilm around the intakes and poured brick cleaner down the strainer inlet. After a soak of about 30 mins I released the clingfilm and caught the fluid in a bucket. No real evidence of anything having taken residence in the channels.

True story, I have a pal who found a small eel in this strainer.

 

[maby]

I was concerned that this may be a problem so at 5 years I wrapped clingfilm around the intakes and poured brick cleaner down the strainer inlet. After a soak of about 30 mins I released the clingfilm and caught the fluid in a bucket. No real evidence of anything having taken residence in the channels.
....

I'm not sure if that is a good idea, sir! Brick cleaner is quite strong acid and a saildrive is aluminium alloy - I think you could easily eat right through the wall of the drive....

 

[johnalison]

People are fond of anecdotal stuff so another to consider is the failure of the P Bracket. On one boat I was helping to deliver there was so much vibration on the shaft we had to get a diver to look and found a fractured P Bracket. Quite expensive to lift out and sort
Not saying it is a regular problem but just google 'broken p bracket ybw' and you will see it is not rare and is one to factor in the mix

A club mate of ours was motoring through Rotterdam and suffered a failed P-bracket. He was quickly towed out of the way and ended up at a yacht club. Members were present and they slipped him and before the owner had blinked they had welded or repaired the part and he was on his way. The club members refused any form of payment.

 

[jordanbasset]

A club mate of ours was motoring through Rotterdam and suffered a failed P-bracket. He was quickly towed out of the way and ended up at a yacht club. Members were present and they slipped him and before the owner had blinked they had welded or repaired the part and he was on his way. The club members refused any form of payment.

Much more generous than the commercial yard who dealt with the one I am thinking of, good to see though, just a question of luck where it happens I suppose

 

[Bobc]

I have first hand experience of 4 saildrive blockages in the past year. 2 of them we managed to clear by using the dinghy pump, one required Seastart and a diver to clear, and the other resulted in a lift-out.

It all depends where you sail and how clean the water is, but muddy rivers with lots of weed seem to cause the most problems.

 

[geem]

Q

People are fond of anecdotal stuff so another to consider is the failure of the P Bracket. On one boat I was helping to deliver there was so much vibration on the shaft we had to get a diver to look and found a fractured P Bracket. Quite expensive to lift out and sort
Not saying it is a regular problem but just google 'broken p bracket ybw' and you will see it is not rare and is one to factor in the mix

P brackets may be an issue but we dont have one. 2” diameter shaft fully enclosed.

 

[Skylark]

I'm not sure if that is a good idea, sir! Brick cleaner is quite strong acid and a saildrive is aluminium alloy - I think you could easily eat right through the wall of the drive....

I did it immediately prior to a new season launch such that all traces would be washed away quickly.

I diluted it to the same concentration as I use to clean the prop. Also, I did a test piece by brushing out-of-the-tin-concentration up the gallery as far as the eye can see. After several minutes there was no reaction so I progressed to clean-out the channels as previously described.

 

[johnalison]

I have first hand experience of 4 saildrive blockages in the past year. 2 of them we managed to clear by using the dinghy pump, one required Seastart and a diver to clear, and the other resulted in a lift-out.

It all depends where you sail and how clean the water is, but muddy rivers with lots of weed seem to cause the most problems.

I had completely forgotten our last time in Salcombe. We had left the Bag to catch the tide and only got to the first corner when the tell-tale sound told me that our inlet was blocked. The dinghy pump wouldn't clear it and we were in the process of trying to arrange a haul-out when a neighbour on the pontoon interrupted his on-board party and donned snorkel and goggles and disappeared below us, returning with an armful of green weed. That is once in about 3,500 hours saildrive motoring.

 

[Baggywrinkle]

Yes sorry for butting in but that statment by Baggy does not hold well for saildrive longevity, 43 year old shaft drive with 5500 engine hours, with new cutless bearing when old wears out and good maintenance, I know nothing about saildrives but to compare I suspect there will be longivety in the shaft , which has had many many years to be perfected

There was nothing wrong with the saildrive ... no bearing play, no funny noises and it was running fine .... it was the engine that was getting on a bit. It all still worked and I sold the lot on to a guy in Denmark. It was a bit smokey but had spent a decade in a Mediterranean charter boat so was a bit abused and unloved. The package to repower made it daft to keep the old saildrive - might as well replace the lot

 

[Baggywrinkle]

If you're worried about weed clogging the saildrive intake, fit a through-hull and use that :encouragement:

 

[lw395]

If you're worried about weed clogging the saildrive intake, fit a through-hull and use that :encouragement:

I've had a couple of water intake blockages with shaft drive.
In either case an artful bodger could probably plumb the engine intake to the sink skin fitting.

I don't think the choice of saildrive or shaft would be decisive in my next choice of boat.