Suitablility of Saildrive for Cruising Boat

[colemj]

I don't know the exact alloy. It is listed as an "aluminum-magnesium" alloy, which the only ones I know are the 5xx.x series. These would be similar to the wrought series in hull plating.

I didn't mention anything about outboards, so don't know why that is directed at me. But I do know many outboards that spend years primarily submerged in saltwater. BTW, it is worse for those to be in/out of saltwater than to stay submerged - unless they get fresh-water flushed between.

I neither like nor dislike saildrives. I'm certainly not a "proponent" Same for shaft drives or any particular engine or transmission. I have owned several of all types. So far, the only transmission problem I have had was with a Hurth gearbox. I don't read anything into that.

I look for good specific engines and transmissions when considering them. For example, the Volvo 200x series were truly bad engines overall. However, the Volvo (nee Perkins) 20x0 series are fantastic engines with none of the issues of their predecessors. Likewise, I would have no problem with a Yanmar 20 saildrive, but not have the 40.

Many, perhaps you, color everything Volvo based on experiences with a particular model/generation or two and do not see things more relatively. I can list you a few Yanmar model horror stories, as well as Westerbeke, etc. Sounds like your friends in the other thread had a few Yanmar issues themselves.

When choosing a boat, if the brand of engine or propulsion system matters, then choose around that - I support that. This leaves out a vast amount of catamarans if one is interested in those. As well as certain brands and models of monohulls. For us, we wanted a catamaran. The issue of saildrives and engine brand were not a problem, but there were very specific individual drives/models that we would not take, and we required a well-maintained system. This only narrowed our choices marginally.

Do you not know anyone at all with saildrives that work well and have no problems (I don't count)? Or does your intense bias only allow you to see and remember those that do have problems? Maybe the S. Pacific is the graveyard for saildrives?

For example, we are sitting in an area right now with probably a thousand or more boats and I would guess that 35-40% of the engines have saildrives (large number of catamarans and they have two each). These saildrive problems that you find so prevalent simply are not occurring here. Boats are moving in and out of yards and no one is working on saildrives. Really. Multiple hundreds of boats in the yards and no one has saildrive problems. The rest are in the water and no one is working on, or talking about, saildrives.

I take that back. There is one boat that took a large lightning strike that blew out everything. They have something wrong with one of their drives. I'm sure a shaft drive would have survived that better.

Mark

[colemj]

Originally Posted by Bulawayo

Hi Mark, Something just does not sound right regarding the painter tearing out the motor / sail drive etc.
Something just is not right. We have motor sailed into heavy drift fishing nets at night and had serious wrap ups. Agreed that our sail drives are between the keels and the spade rudders but it has still been the sail leg that has tangled with the fishing gear. Our cutters proved useless for this situation.
If the Lagoon really did have this occur then it sounds to me as though there was an issue already created that was looking for a reason to happen. In other words it was not the fault of the sail drive. As we all know the Lagoons are one of the most popular cats on the charter market and these must have many foul ups without such a catastrophe (no pun intended) - if this was a real weakness then they would be sinking regularly and there would be no charter market for them. There is something not being told........

I don't know what to tell you - there is a website and thread on this forum documenting it. However it happened, it broke the mounting hole casting around the saildrive and tore it right off the mounts. Perhaps he had a dyneema painter and was going full-bore in reverse?

I too think that in the charter business many people must have wrapped the dinghy painter in the props. It is a design begging for that to happen. Perhaps there is a story not being told, but the pictures and chronicle seems to support the painter problem.

Mark

[colemj]

Originally Posted by Cotemar

Volvo Penta parts cost the same as Yanmar as I have owned both engines.

And I have posted several times on these forums price lists for parts from both showing just that. So has a dealer for both of these brands. Problem is, people believe only what validates their beliefs - facts be damned.

Mark

[belizesailor]

Originally Posted by colemj

OK, saildrives are a really bad idea. More than one shaft drive boat has sunk because a line wrapped around it and pulled the shaft out. So those are a really bad idea too. And Yanmar prices are the same as Volvo's, so it is best to stay away from them. And can you imagine an aluminum hull submerged in salt water? Best to stay away from those.

Yep, the infallible and deep logic in these arguments have convinced me that most boats out there are unsafe for serious cruising.

Mark

I agree both are a bad idea, but damn few production boats out there with neither. However, if I ever get around to building the ultimate cruising cat design in my head, it will have neither.

[colemj]

Originally Posted by belizesailor

However, if I ever get around to building the ultimate cruising cat design in my head, it will have neither.

They had those in the past America's Cup…

Mark

[Ocean Diamond 2]

Originally Posted by colemj

Ann's story of the boat in NSW is disingenuous because that boat reported a problem with the waterpump on their engine, not the saildrive, and with the quality of the service center's work, not the engine itself. They also said they went through 4 Yanmar engines in a single year before going with a Volvo instead - she conveniently left that unstated. Also left out was the fact that there was a fire in the engine room precipitating the damage to the engine.


Mark

Ok guys its my Bad. I write Australian English and I think a bit got lost.

The real problem was the gearbox leaking oil after a $850 engine service by the local Volvo dealer. They said it should come out to replace all oil seals. I said ok because the book says the saildrive rubber hull gasket should be replaced every 7 years. Thats when they stuffed the water pump oil seal and yes, its still not fixed. yes thousands later ( local Agent ).
The engine fire incidently was caused by the exhaust elbow not being replaced at 5 year mark and the vetus water lock box not having water going through it.

My 4 Yanmars were in the Dehler 34 I had and its shaft drive never leaked oil or water but the engines were 2 x 2gm20's + 2 x 3gm30's again I think it was a bad service agent supplier doing work for Yanmar.

Must admit the sail drive does reverse much better that the shaft drive. That might have something to do with the folding props as well.

Oh and when one wraps the painter of a blowup dinghy around the prop and shaft of a hire fleet Bene 411 in the whitsundays to the point the dinghy goes under and the Bene goes up, it dosn't pull the engine of the mounts .

Sorry for being not well written.
Derek.