To repair Yanmar SD50 or "upgrade " to SD 60

[Colin K]

Hi All,
I've been reading with great interest the forum on Yanmar SD 40/50.
Three years ago as part of a refit on my 14m catamaran I decided to upgrade the installed Yanmar 3GM 30's & SD20 sail drives ( 3500 hours & trouble free ) to 3JH5CE & SD50 39 hp Yanmar on the basis of increased power & safety crossing river bars & reef entrances around Australia & the Pacific.
At 350 hours my SD 50's started slipping & have failed to engage forward gear.
It seems that repairs even with new cones & lapping is temporary at best & even the gears may need changing due to them being manufactured using a substandard metal.
Rather than perform repeated expensive repairs I am considering a further "upgrade" to SD60's.They are said to have a different clutch system but have only been available in Europe for 1 year.
I'd be grateful for any information regarding the SD 60 sail drive .Are there any alternative sail drives compatible with the present engines ?

[DotDun]

Originally Posted by Colin K

Hi All,
I've been reading with great interest the forum on Yanmar SD 40/50.
Three years ago as part of a refit on my 14m catamaran I decided to upgrade the installed Yanmar 3GM 30's & SD20 sail drives ( 3500 hours & trouble free ) to 3JH5CE & SD50 39 hp Yanmar on the basis of increased power & safety crossing river bars & reef entrances around Australia & the Pacific.
At 350 hours my SD 50's started slipping & have failed to engage forward gear.
It seems that repairs even with new cones & lapping is temporary at best & even the gears may need changing due to them being manufactured using a substandard metal.
Rather than perform repeated expensive repairs I am considering a further "upgrade" to SD60's.They are said to have a different clutch system but have only been available in Europe for 1 year.
I'd be grateful for any information regarding the SD 60 sail drive .Are there any alternative sail drives compatible with the present engines ?

The SD60 has a plate clutch.

[Oliver L.]

Colin,

there's a detailed description around on how to re-lap the cones. I watched the disassembly on board once, and the next time I'll do it myself - it is definitely not rocket science.

I got one SD40 and one SD50, and I definitely want to be able to fix that myself. Got the lapping paste from the shop that did it the first time.

Oliver

[Colin K]

Thank you Oliver . I think I saw something referable to disassembly elsewhere in the forum. How many hours approx. does lapping last. I'm told it's best not to motor sail , or sail in reverse gear but leave in neutral & when changing gear almost slam it into gear.What do you do?

[bad kitty]

Hi Colin, sorry for the thread hijack but........
We've got SD40's in a cat. Had the slipping cone & repaired that but now the starboard drive sometimes doesn't engage forward gear properly. The flexofold prop seems to turn but we don't get drive. Increase the revs & it suddenly thumps into gear. No apparent slipping this time though?
Is that the same as your failure to engage?
No one here in NZ seems to know what the issue is, although the slipping drive is well known.
Thanks, Bad Kitty

[Colin K]

Hi Bad Kitty,
It all seems to be part of the same problem . I've also had failure to go into gear then on increasing revs forward gear engaged with a loud bang.Rather than put up with the prospect of having repeated failures down the track I'm heading in the direction & taking the risk by installing SD 60's , hoping that the plate clutch will allow motor sailing etc.
Cheers
Colin K

[bad kitty]

OK thanks Colin, that's what I'm thinking also. The SD40's seem to be a disaster, and Yanmar in NZ particularly bad at standing behind their product & it's bad engineering.

[Panache5000]

Hi Bad Kitty.
Refer to my info on the SD50 problems and solving thereof. Posted +- Sept 2013. I had exactly the same engagement problem. Hope yoi come right. PANACHE in USVI

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

[Emerald Sea]

Anyone out there wanting to share their experience with Yanmar's SD-60'S?

[Colin K]

Hi Emerald Sea,
I finally made a decision to install the Sd60's based on the uncertainty of when the re-lapped cones would again fail & the continuing cost.My research indicated that the cones really needed to be replaced & then lapped to bed them in if one wanted to do the repair properly, so repair can be expensive. It was indicated that, particularly with charter yachts, re- lapping was part of the annual service.
With the change over, an adaptor plate is needed with my engines ,39hp 3JH5CE's. Also there is a small variation in gear ratios between the 50 & 60 & at the moment at full revs I exceed 3000rpm which requires a slight increase in prop pitch which can be easily done in water with my Autostream props.I'm relying on the fact that the plate clutch doesn't have the same problems which seems to be the case as it's used in other brands of sail drives,time will eventually tell.I hope this helps, good sailing.
Colin K

[bad kitty]

Hi Colin, any update on the SD60's?
Interested in the same upgrade,
Thanks

[Colin K]

Hi Bad Kitty,
So far no real problems but early days, slightly more vibration than previously but Yanmar engineer checked it out & was satisfied . Only recently got around to increasing prop pitch.Cruising to Tasmania over the next 6 weeks so will give them a better workout.
Cheers
Colin K

[Captain Bill]

Originally Posted by Colin K

Hi Emerald Sea,
I finally made a decision to install the Sd60's based on the uncertainty of when the re-lapped cones would again fail & the continuing cost.My research indicated that the cones really needed to be replaced & then lapped to bed them in if one wanted to do the repair properly, so repair can be expensive. It was indicated that, particularly with charter yachts, re- lapping was part of the annual service.
With the change over, an adaptor plate is needed with my engines ,39hp 3JH5CE's. Also there is a small variation in gear ratios between the 50 & 60 & at the moment at full revs I exceed 3000rpm which requires a slight increase in prop pitch which can be easily done in water with my Autostream props.I'm relying on the fact that the plate clutch doesn't have the same problems which seems to be the case as it's used in other brands of sail drives,time will eventually tell.I hope this helps, good sailing.
Colin K

Colin,
As long as you have autostream props there may be a much cheaper solution. Panache5000 has identified the wear problem associated with the thrust washers and has detailed that in other threads. The problem is essentially limited to the bottom half of the cone clutch which has a spring that is used to disengage the clutch. I just lapped my cone clutches for the first time at about 3000 hours because my clutches were slipping in reverse. Forward was still working fine. The reason I had problems in reverse was that I have autostream props and have them set up for left hand drive. This means that when I am in forward gear my upper cone clutch is engaged which doesn't have the wear/slipping problem identified by Panache5000. If you lap the clutches and switch your props and shift lever to left hand forward drive you could go a very long time before needing to lap them again.

I looked at switching my drives out as well, but apparently Yanmar doesn't normally ship saildrives to the US which are not attached to new engines. It was a 90 day wait with no guarantee of a delivery date to get one shipped from Japan. You might have a similar problem in OZ so make sure if you decide to replace them you ask about delivery time.

[Captain Bill]

Sorry Colin I hadn't noticed the date on your post. I guess you have already made the replacement. It will be interesting to see how the sd60s hold up.

[gatorsailor]

Any new experiences with the SD60's?