Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 18-07-2016, 23:30   #1
Registered User

Join Date: Jun 2016
Location: Mediterranean
Boat: Beneteau Oceanis 45
Posts: 40
Are modern sail-drives less reliable? SD50 SD60

My Yanmar SD60 sail-drive has failed with clutch-slip for the second time in 300 hours, and many friends have similar problems with the much-maligned SD50. In contrast, my old Volvo gearbox was faultless for 4,500 hrs and 15 years, and we never thought about gearbox failures.

We are used to the long warranties and almost perfect reliability of the automotive industry, but the marine gearbox technology seems to be stuck in the 70’s. Since they changed from the clunky but reliable dog clutches, the friction clutches have always been inclined to slip.

The clutches are simply too small to take the torque. In the last 40 years, sail drive gearboxes have become smaller due to improved gear technology, while yachts have increased their engine power. Various designs have tried many ways to reduce slipping, using cones or multi-plates, but always with restricted size between the reverse gears.

My SD60 (built by ZF, similar to the Volvo 130/150S) is very hard to service, because the engine needs to be disconnected and moved forward. The SD50 (made by Yanmar) is a better design, as the shaft is easily removed for servicing the cones.

Reliability seems to be going backwards, is it just my bad luck, or are others having problems as well?
RichMac is offline   Reply With Quote
Old 19-07-2016, 01:17   #2
Moderator
 
noelex 77's Avatar

Cruisers Forum Supporter

Join Date: Jul 2007
Boat: Bestevaer.
Posts: 14,678
Re: Are modern sail-drives less reliable? SD50 SD60

Sail drives do have advantages. They are cheaper, quieter, and take up less space, but I am not convinced the reliability is anything near as good as a conventional gear box and shaft drive system. I have seen too many fellow cruisers with serious and expensive problems.

However, I think as you note, the SD 50 is bit atypical with a particularly poor record. There was some hope that the SD 60 would be much better, but your experience with the SD 60 does not sound promising.
noelex 77 is offline   Reply With Quote
Old 19-07-2016, 04:59   #3
Registered User
 
Emerald Sea's Avatar

Join Date: Feb 2013
Location: Live-aboard Cruiser
Boat: Lagoon 450
Posts: 628
Re: Are modern sail-drives less reliable? SD50 SD60

Quote:
Originally Posted by RichMac View Post
Reliability seems to be going backwards, is it just my bad luck, or are others having problems as well?
Our pair of SD60s are running just over a 1000hrs each and have been champs. Absolutely no issues (knockin on wood). We have met at least 6 other yachts with Yanmar/SD60s and they too are having no issues.
__________________
Steve
SV Emerald Sea
L450
Emerald Sea is offline   Reply With Quote
Old 19-07-2016, 05:24   #4
Registered User
 
Captain Bill's Avatar

Join Date: Apr 2008
Location: Punta Gorda, Fl
Boat: Endeavourcat Sailcat 44
Posts: 3,173
Re: Are modern sail-drives less reliable? SD50 SD60

I've got about 500 hrs on my sd60s and no problems so far. My assessment of sail drives is that they are primarily designed for the needs of the weekend sailor, where it might take 20 years to accumulate 500 hours. They seem to be primarily designed to get one in and out of the slip, not to motor long distances. They probably meet the needs of 99% of their market.
Captain Bill is offline   Reply With Quote
Old 19-07-2016, 05:39   #5
cruiser

Join Date: Oct 2015
Posts: 285
Re: Are modern sail-drives less reliable? SD50 SD60

In my informal lurking observations on this subject, the Internet indicates that it's not the generation, but the brand, of saildrive that indicates reliability.

That is to say, it appears to me that Yanmar saildrives are far more problematic than Volvo saildrives from what i've seen on various fora.

I seem to recall that Mark Cole 'Reach' has come to the same conclusion.

FWIW I have Volvo drives that are as old as my boat (1992). I have recently done a technical modification which I have described elsewhere but essentially they are 'original.' The boat was in charter for its first ten years.
AD28 is offline   Reply With Quote
Old 21-07-2016, 13:47   #6
Registered User

Join Date: Jun 2012
Posts: 62
Re: Are modern sail-drives less reliable? SD50 SD60

i am so surprised that the SD60 also has problems- Actually not surprised! it is still a YANMAR product, although the gearbox is ZF.

However, we have developed the cure for the SD40 & SD50 slipping Cone Clutch problem!!

My earlier posts on this issue describes the reasons why the Cone Clutch starts slipping. In short it is due to play developing caused by the Copper Thrust Washers in the upper Gearbox assembly, combined with limited Gear Selector adjustment.

We have developed a SD40 & SD50 UPGRADE/REWORK KIT that uses THRUST BEARINGS (like VOLVO) in place of the Thrust Washers.
The Bearings allow a much closer setup tolerance, with reduced wear.
The Kit also includes an adjustable Selector Set Screw and Locknut.

Another improvement is an "Open Breathing" system which reduces the possibility of blowing the oil seal between the Engine and the saildrive, and also prevents water being sucked up (when cooling down after use) at the Propeller Seal.

Both my saildrives with over 2000Hrs are fitted with the UPGRADE/REWORK Kit.

If you need any further info, feel free to e mail me on panache5000@yahoo.com
Panache5000 is offline   Reply With Quote
Old 22-07-2016, 00:36   #7
Registered User
 
EWOL Props's Avatar

Join Date: Nov 2015
Posts: 134
Re: Are modern sail-drives less reliable? SD50 SD60

Quote:
Originally Posted by Panache5000 View Post
i am so surprised that the SD60 also has problems- Actually not surprised! it is still a YANMAR product, although the gearbox is ZF.

However, we have developed the cure for the SD40 & SD50 slipping Cone Clutch problem!!

My earlier posts on this issue describes the reasons why the Cone Clutch starts slipping. In short it is due to play developing caused by the Copper Thrust Washers in the upper Gearbox assembly, combined with limited Gear Selector adjustment.

We have developed a SD40 & SD50 UPGRADE/REWORK KIT that uses THRUST BEARINGS (like VOLVO) in place of the Thrust Washers.
The Bearings allow a much closer setup tolerance, with reduced wear.
The Kit also includes an adjustable Selector Set Screw and Locknut.

Another improvement is an "Open Breathing" system which reduces the possibility of blowing the oil seal between the Engine and the saildrive, and also prevents water being sucked up (when cooling down after use) at the Propeller Seal.

Both my saildrives with over 2000Hrs are fitted with the UPGRADE/REWORK Kit.

If you need any further info, feel free to e mail me on panache5000@yahoo.com
This is very interesting Panache5000 !
EWOL Props is offline   Reply With Quote
Old 23-07-2016, 18:05   #8
Registered User
 
Harlequin's Avatar

Join Date: Dec 2014
Location: visiting NZ
Boat: Bavaria Vision 44
Posts: 65
Re: Are modern sail-drives less reliable? SD50 SD60

Can any of this be related to the practice of selecting 'reverse' to lock the prop whilst sailing?

I admit we've always done so, to stop the drive free-spinning and fold our Bruntons Varifold prop, but I've heard advice that suggests this might be bad for the clutch. I'm guessing due to shock loading.

Full disclosure: we've replaced the clutch plates twice on Harlequin's Volvo saildrive in 2,800 hrs / 25,000 nm / 8 yrs. [Also replaced the complete saildrive after the top bearing seized, but that's another story... ]

Interested to hear others thoughts and experience...
Harlequin is offline   Reply With Quote
Old 23-07-2016, 21:17   #9
Registered User

Join Date: Jun 2016
Location: Mediterranean
Boat: Beneteau Oceanis 45
Posts: 40
Re: Are modern sail-drives less reliable? SD50 SD60

Clutch wear could be affected by the style of use. We are in Greece, and the stern first med-mooring method is quite tricky, and needs many more gear changes. With a cross-wind in a small harbour or marina, you have to be quite firm with engine thrust, which could accelerate clutch wear.

All credit to Panache for his excellent work on the SD50, fitting the longer-lasting thrust bearings. But why does it take an owner to solve the problems? Yanmar, Volvo and ZF should be taking responsibility, offering warranty periods of 1000+ hours, and designing the gearbox so there are no claims.
RichMac is offline   Reply With Quote
Old 24-07-2016, 08:12   #10
Registered User

Join Date: Apr 2015
Location: PORT CANAVERAL
Boat: GULFSTAR 53 MOTORSAILER
Posts: 126
Images: 1
Re: Are modern sail-drives less reliable? SD50 SD60

I have a #50,000 plus monohull. My 6.354 perkins diesel and inboard direct drive, with a Velvet Drive transmission with 2:1 reduction gears, now has over 20,000 hours on it, has been around the world twice, and all that has been done is change the trans fluid once a year.
I have friends that have sail drives. It seems that none of them can make 1000 hours without problems. They even have to pull their boat out of the water to work on them.
I think that it is well worth the extra money to buy a boat that does not have a sail drive.
MAJICDAN is offline   Reply With Quote
Old 24-07-2016, 10:34   #11
Registered User
 
Dulcesuenos's Avatar

Join Date: Dec 2010
Location: Western Caribbean
Boat: 38/41 Fountains pajot
Posts: 3,060
Images: 4
Re: Are modern sail-drives less reliable? SD50 SD60

We have 4900 &5300 hours on our yanmar saildrive no major issues, maintenance and seals that's all. They are the smaller ones with dog clutches though.

Sent from my PLT1077G using Cruisers Sailing Forum mobile app
Dulcesuenos is offline   Reply With Quote
Old 25-07-2016, 15:30   #12
Registered User
 
Emerald Sea's Avatar

Join Date: Feb 2013
Location: Live-aboard Cruiser
Boat: Lagoon 450
Posts: 628
Re: Are modern sail-drives less reliable? SD50 SD60

This document is well known to many SD40 & 50 owners with cone clutch issues. Ive posted it again as its been a big aid to many. Go to the link and scroll down to the other link at the bottom of the page.... Yanmar Cone Drive Repair Manual

http://www.sailblogs.com/member/leucat/
__________________
Steve
SV Emerald Sea
L450
Emerald Sea is offline   Reply With Quote
Old 20-09-2017, 17:44   #13
Registered User

Join Date: Sep 2017
Posts: 3
Re: Are modern sail-drives less reliable? SD50 SD60

I own (2) Yanmar SD-60 saildrives on Beneteau Oceanis 45’ sailboats with about 350 hours on the SD-60 saildrives that have failed.

They were installed by the Beneteau USA Factory in May of 2016.

Yanmar last week (August 2017) has confirmed that the SD-60’s have a ram angle/ clutch plate problem…and must only be replaced with serial # 264271 or higher that has the correct redesigned ram clutch angle. (Yanmar has not sent out any Technical Bulletins about this as of August 27, 2017)

The problem presented itself after approximately 4 months of use….but only a few times. We thought it was the 3- blade folding props not opening right away… maybe fishing line on the prop??? After giving a lot of throttle, there would be ‘thud’ sound and go into gear. The noise sounded like it was coming from the prop. Due to our short summer, the boats are laid up ‘sleeping’ from mid-Oct to May. We inspected the props while the boats were on the hard over the winter and they were in perfect working order. The boats went back in the water in May of 2017 and the shifting noise slowly starting getting worse. Some days there were no issues while other days you had to give the engine high RPM’s to get the boat to move forward or in reverse. We were told Yanmar had no SD-60 shifting problems, so it must be the folding prop. We dove on the boats and checked the props again and they were perfect. We were also dealing with loose bolts on the shifter arm which would only let the transmission engage 25% to 40%.
Yanmar did recognize and sent out a Bulletin on July 4, 2017 all Distributors & Dealers.

Last week (August 2017) we contacted Yanmar direct and were told to remove the shift cable and move the shifter by hand. We did and the saildrive transmission would only engage at very high rpm’s and then slam into gear! When in gear, the saildrive will move the boat only in calm conditions, however, if going into a strong headwind or against a strong tide the saildrive transmission starts slipping! Clearly not a safe situation !

I see on the internet that other Beneteau 45’s customer and Yanmar SD-60 customers have been having the same problem for over a year.
I have been a once proud owner of many Beneteau sailboats over the past 30+ years. I would have appreciated being notified about the Yanmar problem from Beneteau and or Yanmar and would have the opportunity to replace the saildrives in the off season.


I have only been purchasing Beneteau / Jeanneau and Yanmar products for my sailboats over the past 30 years and would like to continue to do so. Given my long term relationship with Beneteau and Yanmar and the nature of the problem with the saildrives I would expect that any costs incurred to repair them will be covered under a know defect and be covered under warranty. Beneteau did not answer my email and Yanmar would not pay for the defective saildrives. I can only imagine what will happen to all those boat owners that have the known defective Yanmar SD-60 saildrives in them will the serial #'s below 264271 and want to sell or trade the boat in? Maybe its time to go back to the good old gearbox with a propeller shaft that worked forever???
YanmarSD60 is offline   Reply With Quote
Old 21-09-2017, 00:13   #14
Marine Service Provider

Join Date: Jan 2008
Location: Chessapeake
Boat: Island Spirit 401 Catamaran
Posts: 543
Re: Are modern sail-drives less reliable? SD50 SD60

Sail drives do have a few advantages to an end user but I doubt any naval architect/builder made the decision to use them based on this. The key advantages governing their use in my opinion is that they they allow more design options for interior space and are easier to install (plus probably cheaper).

I am not sure the use of them will ever end particularly if we continue to buy boats using sail drives. The fastest way to end there use is to refuse to consider new boats with sail drives. Builders will get the hint very quickly. A doubt the feedback loop for the used boat market is strong enough to make any difference with builders.
Ostinato is offline   Reply With Quote
Old 21-09-2017, 02:35   #15
Registered User

Join Date: Jun 2016
Location: Mediterranean
Boat: Beneteau Oceanis 45
Posts: 40
Re: Are modern sail-drives less reliable? SD50 SD60

[QUOTE=YanmarSD60;2483221]
Yanmar last week (August 2017) has confirmed that the SD-60’s have a ram angle/ clutch plate problem…and must only be replaced with serial # 264271 or higher that has the correct redesigned ram clutch angle. (Yanmar has not sent out any Technical Bulletins about this as of August 27, 2017)

Our SD60 was repaired for the second time last year, when they replaced the clutches. There are small ball bearings that run in angled grooves, which jack the clutch plates together. The new clutch had the ball grooves at a different angle, to increase the jacking force. Another 150 hours, and they are going well.

The test for a slipping clutch is how strongly it engages when put into gear. Before ours failed, the gear engagement was really soft, as it took a while to engage. Now with the improved clutch, it engages with a satisfying clunk. Hopefully it will last!
RichMac is offline   Reply With Quote
Reply

Tags
sail, sd50

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
boom less, track less staysail advice Abrain Deck hardware: Rigging, Sails & Hoisting 17 19-12-2013 08:57
450: Lagoon 450 - SD60 sail drive roetter Lagoon Catamarans 4 07-12-2013 17:00
used SD50 or new SD60? kabrisle Engines and Propulsion Systems 2 07-12-2013 16:58
For Sale: Leopard 48-Like New Sail, Boom, +SD50 Sail Dr Starblossom Classifieds Archive 0 03-09-2013 06:08
Sail-Drives or Shaft Drives? RubyBishop Multihull Sailboats 24 07-09-2009 09:14

Advertise Here


All times are GMT -7. The time now is 06:32.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.