mjd
New Member
Considering buying a boat that has been fitted with Volvo Penta 2001 9hp saildrive engine. Any info or comments on same would be appreciated. Are there any advantages/disadvantages over "normal" drive engines?
Saildrive engines
- Thread starter mjd
- Start date
Parsonsheath
Well-Known Member
I have a saildrive, cons, they need the seal done every 7 years, pros? less chance of leaks, and no long tubes to be knocked and bend long shafts
Dipper
Well-Known Member
I have a Volvo 2001 with 120S saildrive.
Disadvantages
Big hole in the boat if the seal fails but I have never heard of one failing.
Cost of replacing seal every 7+ years.
Saildrive leg expensive to repair and potentially prone to corrosion if anodes fail.
Advantages
Easy for boat builder to install - that's why they like them.
Less vibration and noise transmitted to the hull.
Propeller is deep in the water.
Less (negligible) prop walk because propeller is so deep.
Propeller close behind a fin keel so less likely to snag?
No prop shaft to bend, leak, break away.
Disadvantages
Big hole in the boat if the seal fails but I have never heard of one failing.
Cost of replacing seal every 7+ years.
Saildrive leg expensive to repair and potentially prone to corrosion if anodes fail.
Advantages
Easy for boat builder to install - that's why they like them.
Less vibration and noise transmitted to the hull.
Propeller is deep in the water.
Less (negligible) prop walk because propeller is so deep.
Propeller close behind a fin keel so less likely to snag?
No prop shaft to bend, leak, break away.
oldsaltoz
Well-Known Member
G'day mjd,
We run twin saildrives on our Stephans / Lees Catamaran, The last Mono hull we had also had a saildrive with fin keel and skeg,
Cons:
Access in a monohull under 30 feet can be a problem if installed under the cockpit and well aft. Regular anode check are critical. Seal replacement is required by some insurance firms if you have no history of last replacement date, though it's not the end of the world if you have to replace one.
Pros:
We have ours mounted in their own rooms, bulkhead fore and aft, so no chance of a sinking, no diesel fumes or fuel smells. If removed need or no lining up when re fitting. Low noise, Low vibration. parts availability is good around the world, but not cheap (is anything in this industry)?
By the way the rubber seal is in fact a double layer seal, it also has a detector that will let you know if any water gets between the two layers, so are very safe.
Check the condition of the water intakes on the leg, also the area around the prop shaft, they are the first to show signs of corrosion. We converted ours to pick up raw water via standard thru hull fittings located behind the keels and have never had a blockage or overheating problem, and almost unbelievable on a Volvo.
To avoid some mess in the Monohull bilges, we installed a clear hose that ran from the front of the engine box to a much lower point near the keel so any trace of oil was contained, it had a small tube running up the mast to indicate when / if, it needed cleaning out.
In general sail drives can be a little deeper than a prop on a shaft, however this has it's own advantages and disadvantages. Provided they are above the keel they should be fine. One last thing to look for, the seal around the leg on the underside of the hull is just a patch of rubber (or other flexible material) that is glued to the hull, it should have a simple slot cut in that hugs the leg profile but no be sealed to the leg, or you may end up re sticking it to the hull several times a season.
Hope this helps.
Avagoodweekend......
We run twin saildrives on our Stephans / Lees Catamaran, The last Mono hull we had also had a saildrive with fin keel and skeg,
Cons:
Access in a monohull under 30 feet can be a problem if installed under the cockpit and well aft. Regular anode check are critical. Seal replacement is required by some insurance firms if you have no history of last replacement date, though it's not the end of the world if you have to replace one.
Pros:
We have ours mounted in their own rooms, bulkhead fore and aft, so no chance of a sinking, no diesel fumes or fuel smells. If removed need or no lining up when re fitting. Low noise, Low vibration. parts availability is good around the world, but not cheap (is anything in this industry)?
By the way the rubber seal is in fact a double layer seal, it also has a detector that will let you know if any water gets between the two layers, so are very safe.
Check the condition of the water intakes on the leg, also the area around the prop shaft, they are the first to show signs of corrosion. We converted ours to pick up raw water via standard thru hull fittings located behind the keels and have never had a blockage or overheating problem, and almost unbelievable on a Volvo.
To avoid some mess in the Monohull bilges, we installed a clear hose that ran from the front of the engine box to a much lower point near the keel so any trace of oil was contained, it had a small tube running up the mast to indicate when / if, it needed cleaning out.
In general sail drives can be a little deeper than a prop on a shaft, however this has it's own advantages and disadvantages. Provided they are above the keel they should be fine. One last thing to look for, the seal around the leg on the underside of the hull is just a patch of rubber (or other flexible material) that is glued to the hull, it should have a simple slot cut in that hugs the leg profile but no be sealed to the leg, or you may end up re sticking it to the hull several times a season.
Hope this helps.
Avagoodweekend......
bigwow
Well-Known Member
My Volvo saildrive rubber seals, as far as I know, are not double layer with a detector. But like you my engines are in their own watertight compartments each with manual & electric pumps
Dipper
Well-Known Member
Agreed. The Volvo ones are single seals. The Yanmars are double seals with a sensor between. I don't know about any others.
