Saildrives

[Tranona]

How do you work out that stern drives are troublesome compared to saildrives? Do you have proof to back up that claim? From my limitied experience looking around Curacao Marine this summer, the number of stripped down saildrives from catamarans was remarkable. I dont have statistics but there were over a dozen stripped out compared to a couple of conventional drives having cutlass bearings replaced. If it takes two guys a day to replace the rubber then that is a serious cost. I replaced my cutlass bearing in less than two hours. In addition, the corrosion potential with aluminium under water has to be taken seriously. I know of one ten year old boat with a saildrive who didnt look after the corrosion aspects and has had to have a new saildrive.

I could equally take you around yards here with many 30 and 40 year old saildrives that have probably never been removed since new and still functioning. Follow this forum for a little while and observe all the issues people have with cutless bearings, P brackets, stuffing boxes, bent shafts etc.

Conventional shaft drives have the advantage that the individual components are relatively cheap and easy to replace, but that does not mean they are trouble free.

The potential corrosion issue is well known and can be avoided by following the service recommendations. Citing someone who did not do this as a negative is not really fair when replacing anodes, particularly on drives (Volvo) built since 2005 with the larger anodes, is not a chore. I have yet to replace the anode on my boat which has been in the water continually since August 2015 and when last hauled (June 2018) was still less than 50% eroded.

Nothing is perfect and there are always pros and cons of particular products, but the doom and gloom merchants have been railing against saildrives since they were introduced nearly 40 years ago and they now dominate the European market. Suggests there are many happy users who wonder what the fuss is about.

 

[geem]

I could equally take you around yards here with many 30 and 40 year old saildrives that have probably never been removed since new and still functioning. Follow this forum for a little while and observe all the issues people have with cutless bearings, P brackets, stuffing boxes, bent shafts etc.

Conventional shaft drives have the advantage that the individual components are relatively cheap and easy to replace, but that does not mean they are trouble free.

The potential corrosion issue is well known and can be avoided by following the service recommendations. Citing someone who did not do this as a negative is not really fair when replacing anodes, particularly on drives (Volvo) built since 2005 with the larger anodes, is not a chore. I have yet to replace the anode on my boat which has been in the water continually since August 2015 and when last hauled (June 2018) was still less than 50% eroded.

Nothing is perfect and there are always pros and cons of particular products, but the doom and gloom merchants have been railing against saildrives since they were introduced nearly 40 years ago and they now dominate the European market. Suggests there are many happy users who wonder what the fuss is about.

I am not going to disagree with what you say above. Its when you state a matter of fact that is clearly unsupported or plain wrong that I take issue. This is what you did further up the thread saying that saildrives are more reliable than conventional sterngear. That simply is not true

 

[RichardS]

Having usually serviced all my past boat engines myself ' IF' I buy this boat many suggest getting the engine and saildrive serviced, but other than changing the saildrive oil what else is there to service on a saildrive ?

As Dipper suggests, unless they have been changed in the last year or two, it is probably worth replacing the two shaft seals. Definitely do this if there is the slightest hint of cloudiness in the saildrive oil. It's not a difficult job.

I believe that the Yanmar recommendation is to change the seals every two years although that seems a bit OTT to me.

Richard

 

[scottie]

As Dipper suggests, unless they have been changed in the last year or two, it is probably worth replacing the two shaft seals. Definitely do this if there is the slightest hint of cloudiness in the saildrive oil. It's not a difficult job.

I believe that the Yanmar recommendation is to change the seals every two years although that seems a bit OTT to me.

Richard

Yanmar painted themselves into a corner when they badmouthed Volvo when they introduced the saildrive concept which is why they also have sensors in the gaiter area
Mercury did the same when the outdrive was first produced

 

[DJE]

My mate who's a full time boat mechanic said "It's a day and a half for a fitter and a labourer." He was the fitter, I was the labourer and his timing was spot on.

 

[maby]

Mechanically, I prefer the shaft drive - a lot simpler to maintain and less to go wrong. But handling is the big advantage for saildrives - with the prop further forward and lower, there is virtually no propwalk. If the boat I wanted came in both saildrive and shaft drive options, I would probably go for the shaft, but I would not let a saildrive stop me buying a boat if I liked everything else about it.

The problem with saildrives is the short replacement interval for the seal recommended by the manufacturers. Yanmar specify five years and Volvo only extend this by a couple of years. There are plenty of reports around from owners who have replaced seals at 15 or 20 years old that they were as good as the new unit that they were about to fit, but your insurer is likely to insist on replacement to the manufacturer's recommended schedule.