Saildrive - for and against

eddystone said:
I have just been on a diesel maintenance course and the instructor wasn't very keen on saildrives - I think he believed that the seal was too high a risk.
That apart, as one of the boats I am looking at has a saildrive, I wondered how much difference it would make to annual servicing/winterisation routine. The course gave me the confidence to do this myself and save a fair wad of money and the only thing I can see as different is the fact the gearbox oil has to be changed when it's out of the water. However, I may have misunderstood but is the water inlet on the leg the main cooling inlet for the engine. I had intended to keep the boat in the water all year round apart from a month or so lift out for maintenance and would fill the raw water cooling system with fresh water/antifreeze mix then when I came to use the boat in winter I would reconnect the raw water inlet etc. and re-winterise when I left. If the raw water inlet is inaccessible way down in the leg, that isn't feasible.
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I have had saildrive boats for12years and always keep the boat in the water over winter. Have never yet winterised the engine, it is a lot warmer in than out.
 
Very comprehensive thread! One issue which may occur, and from memory I think it was forumite Saxon Pirate who confirmed the diagnosis I had then made.Water was squirting out of the engine bearers and the aft cabin bilges were full, tasted, seawater, oops!
Seems if you hit enough semi submerged logs, tree branches or whatever, the bond, where the bearer module is bonded to the hull at the exit aperature of the saildrive leg can fail.
The ingress of water was a worry , easily disposed of by sponge and bucket.Upon lifting the vessel,examination of the area of hull/bearer join revealed a fissure on the aft portion, undoubtedly caused by the whole assembly trying to respond to a serious impact.The outer flange bonding was not affected at all.The repair comprised: flushing with fresh water,drying,grind back as neccessary for keying, glass tape, epoxy layer over.I lost the fairing piece on the outside of the hull subsequently, one part glue not seemingly doing the job.However I found wet suit material as a substitute is just as effective and bonds well with normal neophrene glue.
 
eddystone said:
I have just been on a diesel maintenance course and the instructor wasn't very keen on saildrives - I think he believed that the seal was too high a risk.
That apart, as one of the boats I am looking at has a saildrive, I wondered how much difference it would make to annual servicing/winterisation routine. The course gave me the confidence to do this myself and save a fair wad of money and the only thing I can see as different is the fact the gearbox oil has to be changed when it's out of the water. However, I may have misunderstood but is the water inlet on the leg the main cooling inlet for the engine. I had intended to keep the boat in the water all year round apart from a month or so lift out for maintenance and would fill the raw water cooling system with fresh water/antifreeze mix then when I came to use the boat in winter I would reconnect the raw water inlet etc. and re-winterise when I left. If the raw water inlet is inaccessible way down in the leg, that isn't feasible.
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Don't let a saildrive put you off a boat. They are well tried and tested.
 
Noisy sailing

One point that hasn't been made but was emphasised to me on my Volvo saildrive years ago was that you aren't supposed to put the drive in gear when sailing. A lot of people do that to get rid of the noise of the prop turning when under sail but it puts a sideways shear force on the saildrive leg and can jam it in gear. You have to get used to the noise.
 
The procedure seems to be as follows:

Get a plastic nipple of the same size and thread as the drain plug.
Fit hose to nipple. The hose has to be long enough to reach to the pontoon.
Fill the saildrive completely and close it.
Dive under the boat and unscrew the drain plug. Since water is heavier than oil it won't get into the saildrive.
Attach nipple with hose and get onthe pontoon.
Open oil filler cap
Suck out the old oil via hose and keep topping up with fresh oil.
Continue until all the old oil has been drained.
Shut oil filler cap.
Go for another swim and replace the drain plug.
Open oil filler cap and check for correct oil level.
Have a drink, you've deserved it!
 
2nd_apprentice said:
The procedure seems to be as follows:

Get a plastic nipple of the same size and thread as the drain plug.
Fit hose to nipple. The hose has to be long enough to reach to the pontoon.
Fill the saildrive completely and close it.
Dive under the boat and unscrew the drain plug. Since water is heavier than oil it won't get into the saildrive.
Attach nipple with hose and get onthe pontoon.
Open oil filler cap
Suck out the old oil via hose and keep topping up with fresh oil.
Continue until all the old oil has been drained.
Shut oil filler cap.
Go for another swim and replace the drain plug.
Open oil filler cap and check for correct oil level.
Have a drink, you've deserved it!
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Apprentice, your translation is not half so amusing as the original.
 
stuartwineberg said:
One point that hasn't been made but was emphasised to me on my Volvo saildrive years ago was that you aren't supposed to put the drive in gear when sailing. A lot of people do that to get rid of the noise of the prop turning when under sail but it puts a sideways shear force on the saildrive leg and can jam it in gear. You have to get used to the noise.
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A free wheeling prop slows you down I always lock my saildrive in gear while sailing, I think the foregoing is nonsense I'm afraid.
 
savageseadog said:
A free wheeling prop slows you down I always lock my saildrive in gear while sailing, I think the foregoing is nonsense I'm afraid.
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No idea about saildrives (and I have a folding prop so the issue doesn't arise) but Yanmar definitely say that their shaft gearboxes must be left out of gear while sailing. I have a copy of the technical bulletin at home.

Pete
 
stuartwineberg said:
One point that hasn't been made but was emphasised to me on my Volvo saildrive years ago was that you aren't supposed to put the drive in gear when sailing. A lot of people do that to get rid of the noise of the prop turning when under sail but it puts a sideways shear force on the saildrive leg and can jam it in gear. You have to get used to the noise.
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If you have folding prop, VP say put in reverse when sailing.
 
True, MSA08-003 from Yanmar says that their engines must never be put in gear while the engine is off. Hurth states that their boxes must never be in fwd when off, but reverse is OK.
So to me Yanmar engines are not compatible with folding propellers :)

So I guess it's very important to read the manual for your specific gearbox/engine combo
prv said:
No idea about saildrives (and I have a folding prop so the issue doesn't arise) but Yanmar definitely say that their shaft gearboxes must be left out of gear while sailing. I have a copy of the technical bulletin at home.

Pete
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JomsViking said:
True, MSA08-003 from Yanmar says that their engines must never be put in gear while the engine is off.
So to me Yanmar engines are not compatible with folding propellers :)
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I don't think that follows. What they don't want is the shaft trying to spin with the gearbox locked. But if the prop is folded, then the shaft won't be trying to spin.

Pete
 
True. But sometimes (and I've experienced this on several boats) the prop unfolds and start spinning when not in reverse. Should've explained that.

prv said:
I don't think that follows. What they don't want is the shaft trying to spin with the gearbox locked. But if the prop is folded, then the shaft won't be trying to spin.

Pete
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:confused: But You're not allowed to put the Yanmar gears in reverse when sailing and engine is off, so following their requirement the folding propeller starts spinning.. (Am I being daft and/or missing something in translation??)

prv said:
But if it is in reverse, then it's not going to start spinning.

Pete
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