Yanmar SD50 Saildrives - Have the Cone Clutch Problems Been Solved ?

[Fantazia]

Hi Guys,
Thanks for the advice. To keep all you fellow "owners" up to speed with Yanmar. The drive is working now but still "boiling " the oil. Yanmar has "no idea" what the problem is and "by the way they just came out of warranty', The Outcome: I'll be able to buy a new leg for $800 off the published price and Mackay Marine who did the original job and has this week changed owners, "will fix it simply for the price of their labour'. This one will bite me at the worst possible moment so I guess I'll just be the owner and take it smiling. Watch out for Yanmar and their design fault and their warranty and their agents and their mechanics.

[mdsailors]

Hi, We have a 2011 St Francis 50 based near Annapolis on the Chesapeake Bay. We noticed an overall loss of speed and eventually slipping when we engaged the starboard engine. They are 54 hp Yanmars with the SD 50 sail drives. They began to slip about a month ago at around 700 hours. We have been in contact with the Yanmar dealer in Capetown, South Africa that sold the units to St Francis and they suggested we have them replaced , take alot of pics, save the old clutches and send everything back to them and they would submit a warranty claim for us. Do anyone have any advice that might help us avoid the above referenced process? Please feel free to share with us any and all suggestions Thanks

Steven Carroll
SV Paradigm Shift
Annapolis

[telecam]

I have a Beneteau Oceanis 41 just over 9 month old and less than 200hrs on the engine and my Yanmar SD50 saildrive is slipping in forward. Need to get the boat hauled out for repair. Not happy at all Anyone knows what is the standard warranty on Yanmar?

[Captain Bill]

Originally Posted by telecam

I have a Beneteau Oceanis 41 just over 9 month old and less than 200hrs on the engine and my Yanmar SD50 saildrive is slipping in forward. Need to get the boat hauled out for repair. Not happy at all Anyone knows what is the standard warranty on Yanmar?

I don't know what the standard warranty is, but one does not typically need to pull the boat out of the water to service the cone clutches. That whole assembly is removeable from inside the boat and does not even require the engine to be removed from the drive. If a mechanic is telling you that you need to have the boat hauled to do this repair,you might want to see about another mechanic. My experience is that it's not hard to find a yanmar mechanic that knows what he's doing with standard engines and transmissions, but very few know much about saildrives. Maybe you should ask the mechanic how many cone clutches he has serviced. I once made the mistake of going to a yanmar certified mechanic to get some work done on one of mine. When he was finished he happenned to casually mention that this was the first saildrive he had ever worked on. That repair lasted less than 100 hours.

[Panache5000]

The "slipping" or partial engagement of the Cone Clutch is caused by the vertical play on the centre shaft along which the cone moves in a spiral fashion. The shaft is assembled by Yanmar with too much free-play, which is exaggerated by the initial "bedding in" wear of the copper Thrust Washers and the lower Collar & C-clips.. Yes YANMAR uses thrust washers, and not Thrust Bearings! The Thrust washers come in a range with 0,5mm thickness increments. This is too much in some instances, especially on a new unit which still has to "wear in".
The reason that slippage normally originates in FWD, is that the selector has to move the Cone down, (against the spring), and if there is too much vertical free play on the centre shaft, the Cone is still "lifting" the centre shaft, causing the selector to dis-engages before the Cone has made firm contact with the Cone Cup.
The solution is to reduce the vertical free play (+-0,2mm) on the Centre Shaft, lapping the Cone, and re-assembly. END of problem!!

I have done my SD50 in this fashion a year ago, and all is still 100%.

NOTE; We are in the process of introducing a rework kit for the SD40/50 consisting of Thrust Bearings, reworked lower Collar and Top Nut.

Regarding the oil, I still use Synthetic. (Too scared to use to SAE 90!!)

[telecam]

Thanks for all the answers guys, will check with mechanic, he is now saying it could be the prop....

[Captain Bill]

Originally Posted by Panache5000

The "slipping" or partial engagement of the Cone Clutch is caused by the vertical play on the centre shaft along which the cone moves in a spiral fashion. The shaft is assembled by Yanmar with too much free-play, which is exaggerated by the initial "bedding in" wear of the copper Thrust Washers and the lower Collar & C-clips.. Yes YANMAR uses thrust washers, and not Thrust Bearings! The Thrust washers come in a range with 0,5mm thickness increments. This is too much in some instances, especially on a new unit which still has to "wear in".
The reason that slippage normally originates in FWD, is that the selector has to move the Cone down, (against the spring), and if there is too much vertical free play on the centre shaft, the Cone is still "lifting" the centre shaft, causing the selector to dis-engages before the Cone has made firm contact with the Cone Cup.
The solution is to reduce the vertical free play (+-0,2mm) on the Centre Shaft, lapping the Cone, and re-assembly. END of problem!!

I have done my SD50 in this fashion a year ago, and all is still 100%.

NOTE; We are in the process of introducing a rework kit for the SD40/50 consisting of Thrust Bearings, reworked lower Collar and Top Nut.

Regarding the oil, I still use Synthetic. (Too scared to use to SAE 90!!)

This is interesting information, as I have had my first evidence of slipping on my sd40, but in reverse only. As the drive has about 2000 hours on it I guess I have been lucky. It looks like a lapping and/or cone replacement is in my near future. So who are the we producing the rework kit and when might it be available? Also what synthetic do you use and how often do you change the oil? You can answer via PM if you would like.

Bill

[Kiwikat]

Originally Posted by Captain Bill

This is interesting information, as I have had my first evidence of slipping on my sd40, but in reverse only. As the drive has about 2000 hours on it I guess I have been lucky. It looks like a lapping and/or cone replacement is in my near future. So who are the we producing the rework kit and when might it be available? Also what synthetic do you use and how often do you change the oil? You can answer via PM if you would like.

Bill

Please, I was wondering the same as we are about to haul out and get some major work done. Perhaps we may hold off if this rework kit is becoming available soon.

[AussieWayne]

Originally Posted by Panache5000

The "slipping" or partial engagement of the Cone Clutch is caused by the vertical play on the centre shaft along which the cone moves in a spiral fashion. The shaft is assembled by Yanmar with too much free-play, which is exaggerated by the initial "bedding in" wear of the copper Thrust Washers and the lower Collar & C-clips.. Yes YANMAR uses thrust washers, and not Thrust Bearings! The Thrust washers come in a range with 0,5mm thickness increments. This is too much in some instances, especially on a new unit which still has to "wear in".
The reason that slippage normally originates in FWD, is that the selector has to move the Cone down, (against the spring), and if there is too much vertical free play on the centre shaft, the Cone is still "lifting" the centre shaft, causing the selector to dis-engages before the Cone has made firm contact with the Cone Cup.
The solution is to reduce the vertical free play (+-0,2mm) on the Centre Shaft, lapping the Cone, and re-assembly. END of problem!!

I have done my SD50 in this fashion a year ago, and all is still 100%.

NOTE; We are in the process of introducing a rework kit for the SD40/50 consisting of Thrust Bearings, reworked lower Collar and Top Nut.

Regarding the oil, I still use Synthetic. (Too scared to use to SAE 90!!)

Panache is there any further update to this with regards to the rework kit and also how one reduces the free play on the centre shaft?
Wayne

[bad kitty]

Originally Posted by Panache5000

I have two year old SD50's The one does not engage in forward or revese when I put it into gear, I have to either blip the throttle or try again. Once it does engage in gear however, it does not slip. Is this a case of having to lap the cones?? Would appreciat advice.

Hi Panache, did you ever get the answer to this as you worked thru your problem?
We have a SD40 that sometimes won't engage into forward gear.
Increase revs & it then thumps into forward. No slippage once it's going though.
Any ideas?
Thanks,

[Panache5000]

Regarding the repair kit: we did not realize that so many boats have the same problems that we experienced. We initially considered putting a kit together, but even then the adjustment & shimming is critical. If the repair is left to some of the so-called technicians that we have come across in the Caribean, the problem may not be solved!!
We are therefore reluctant to put a kit together at this stage.
My advice is to follow the adjustment & shimming

according to my previous link.

There is also the oil loss/leak at the flywheel. This is another issue, also solved with a breather.

Sent from my GT-I9082L using Cruisers Sailing Forum mobile app

[Captain Bill]

Panache, I was wondering why I was not having problems in forward as so many other people have had. I just realized the answer, my SD40s are set for CCW rotation which means my forward gear is engaging the upper cone and gear, not the bottom cone. I am currently experiencing intermittant problems in reverse in my port drive. How does one go about ordering thrust washers of different thicknesses, my parts catalog only shows one part number?

[Panache5000]

This supports my case regarding the play on the vertical shaft!
Not sure about he diff Yanmar part no fir thrust washers. When I ordered there were a number of diff thickness in kit.
Hope you come right. PSBACHE

Sent from my GT-I9082L using Cruisers Sailing Forum mobile app

[Captain Bill]

Originally Posted by Panache5000

This supports my case regarding the play on the vertical shaft!
Not sure about he diff Yanmar part no fir thrust washers. When I ordered there were a number of diff thickness in kit.
Hope you come right. PSBACHE

Sent from my GT-I9082L using Cruisers Sailing Forum mobile app

It certainly does support your case. I started a poll to see if people with CCW props were having less problems with the sd40/50 than people with CW props, but so far no one is putting in their experiences.

[LHH]

I purchased a Beneteau First 40CR (2012 model) three months ago with 150 hours on the engine. The boat is great and the Yanmar SD-50 saildrive started giving me problems almost immediately. It now only shifts into forward occassionally and is completely unreliable. I purchase this basically new boat to avoid problems such as this.

If you have the choice I would recommend avoiding the Yanmar SD-50 saildrive at all cost. Yanmar is saying the saildrive is not covered under warranty anymore and is not standing behind their product at all. If I had suspected this might happen I would have not purchased the boat. I now have an expensive and labor intensive saildrive headache to figure out.

Beneteau made a mistake using the Yanmar SD-50 saildrives. Mine failed before 160 hours of service and I have not had anything caught in the propeller. I have only used the boat about six times and every time used the engine in a very standard low impact way. I just wish Yanmar would stand behind their product.