SD50 Cone clutch problem

[srah1953]

Hi. I have a 2011 409 with the SD50 Saildrive. I apologise if this seems a stupid question.
How would I know if the cone clutch is slipping? ie, how would it manifest itself? What happens if you ignore it, in long or short term?
Does this problem affect all SD50's, the majority of them or just some?
Thanks for any info you can provide for this ignoramus.

[MalcolmP]

Nov 7, 2018 12:01:37 GMT srah1953 said:

Hi. I have a 2011 409 with the SD50 Saildrive. I apologise if this seems a stupid question.
How would I know if the cone clutch is slipping? ie, how would it manifest itself? What happens if you ignore it, in long or short term?
Does this problem affect all SD50's, the majority of them or just some?
Thanks for any info you can provide for this ignoramus.

Not a stupid question at all. In fact I don't think there are any stupid questions at all about boats. They are all complex and even identical boats may behave differently, this forum really is all about helping to get answers, but even then you may well get very different opinions. Please ask away.

Back to slipping cone clutches. I have a 2008 39i with the Yanmar 3JH4E engine which has a standard prop shaft and a cone clutch Kanzaki gearbox that I changed out 2 years ago. I am therefore not talking about the SD50 specifically, but my understanding is that the principle behind both standard gearbox and saildrive on the cone clutch is the same.

Our problems first were noticeable in it taking time to engage forward drive, IE shift the lever and increase the revs, but that did not always result in increase in speed through the water, just engine noise, although I did not notice any extreme noise say compared with a slipping drive belt.

After a little while the prop would bite and once the slipping had stopped you could get full speed under most conditions. I probably had the unit slipping for a season and gradually it got harder and harder to get drive, I would put it into neutral then back into forward several times, then there might be a clunk and off we would go, not pleasant in a marina or tight locations. Always seemed to engage fine in reverse, guess the polishing microscopically is in one direction.

If you have something similar I would expect it will just get worse and worse, so you will need to bite the bullet 

If you have some engineering skills it is quite feasible to do - there is a great article by Rick James here: www.jeanneau-owners.com/hintsandtips/yanmarconeclutch.html

sure others will add their thoughts

Good luck 

[jy51]

Nov 7, 2018 12:01:37 GMT srah1953 said:

Hi. I have a 2011 409 with the SD50 Saildrive. I apologise if this seems a stupid question.
How would I know if the cone clutch is slipping? ie, how would it manifest itself? What happens if you ignore it, in long or short term?
Does this problem affect all SD50's, the majority of them or just some?
Thanks for any info you can provide for this ignoramus.

You don’t, or to be more precise, not in most cases.   A slipping clutch can sometimes be detected by the change in speed or noise, however, in most cases the first you realise there is a problem it’s too late. Gaining forward drive can be hit and miss until it refuses altogether, but in many cases reverse will still function for a while.  Eventually all SD50 cone clutches will fail after excessive use, I believe the serviceable life of this clutch is about 500 hours but I know of some that have only lasted a few hours and others that seem to go on forever. My own failed at 550 hrs.  The SD50 is not an item to neglect, changing the oil annually is a must and should be done from the bottom up to expell any trapped air in the oil ways.  Changing seals at the first sign of leaks is essential.

Most Yanmar dealers will tell you that to removing the cone clutch will require separating the engine from the sail drive, in most cases this can only be done on the hard and greatly adds to the labour cost. This is NOT TRUE I have done it myself with only a few basic tools Without moving the engine and with the boat still afloat.  Once the clutch is withdrawn a compression tool is required to separate the cone, most car service garages have the facilities to carry this out.  Once removed it is possible to lap the cone with grinding paste or replace it.  Personally I would recommend that if your boat has more than 500 hours change the clutch.  

[rick63]

Hi ,

I wrote the hints and tips article mentioned by Malcolm. I am happy to report that since I completed the work late in 2017 the engine has done another 300 or so hours without any problems. As mentioned above you can remove the clutch for lapping without separating the engine. I needed to do the complete job and move the engine as I needed to replace the input shaft seal as well as the cone clutch repair.

Rick

[MalcolmP]

Mar 26, 2019 9:42:50 GMT rick63 said:

Hi ,

I wrote the hints and tips article mentioned by Malcolm. I am happy to report that since I completed the work late in 2017 the engine has done another 300 or so hours without any problems. As mentioned above you can remove the clutch for lapping without separating the engine. I needed to do the complete job and move the engine as I needed to replace the input shaft seal as well as the cone clutch repair.

Rick

Thanks for the update, Good news, I may follow in your footsteps at some point

Malcolm

[MalcolmP]

Well hopefully there is now a good solution to the SD50 clutch problem (also affects SD40) as an upgrade kit that should eliminate future problems that has been developed by Gideon Coetzee. The video below explains the modification and demonstrates how it may be fitted.





Gideon developed this initially for his own use, but has subsequently supplied over 200 units worldwide, he can be contacted by email: saildrives"at"yahoo.com


There is also a useful video below showing how to remove the clutch components whilst afloat.

 

[StillREEL]

+1

[rick63]

After 1050 hours and lapping the cones twice i have now fitted the modification kit supplied by Gideon. The kit was supplied with very detailed instructions as well as the video. I fitted all the mods, thrust bearings, adjustable selector screw and the gearbox vent pipe. The boat was relaunched last week and did a three hour run this morning back to my home marina. All appeared well with no issues to report. Interested now to see how many hours it lasts for. SD50 fitted to a 2012 SO409.

Rick

[NZL50505]

Key question though - what oil did you put back into it?

GL5 is a no-no. You need to use GL4.

[dbostrom]

Would be nice to see a retrofit kit for the shaft Kanzaki. This has been a weak point in our boat (to the point that we have a spare on hand because while swapping transmissions is a snap, getting another in a hurry is a whole different story especially when the boat is a charter flight distant). 

[MalcolmP]

Apr 12, 2021 23:57:26 GMT dbostrom said:

Would be nice to see a retrofit kit for the shaft Kanzaki. This has been a weak point in our boat (to the point that we have a spare on hand because while swapping transmissions is a snap, getting another in a hurry is a whole different story especially when the boat is a charter flight distant). 

Doug, great minds think alike! In fact I discussed this with Gideon who makes the SD50 kits back in 2019 and he thinks it is feasible, but would need a unit to experiment on of course. I have just sent him a a follow up note, to see if he still is interested in investigating, if he can get hold of an existing Kanzaki KM35P gearbox.

If you don't have it the workshop manual for our gearboxes can be downloaded here: www.hughes38.com/wp-content/uploads/2016/02/KM-Series-Service-Manual-incl-KM35P.pdf

Will update this thread when I hear back from Gideon.

Malcolm

PS I have also just sent you a message with an idea...

[dbostrom]

Apr 13, 2021 8:48:54 GMT MalcolmP said:

Apr 12, 2021 23:57:26 GMT dbostrom said:

Would be nice to see a retrofit kit for the shaft Kanzaki. This has been a weak point in our boat (to the point that we have a spare on hand because while swapping transmissions is a snap, getting another in a hurry is a whole different story especially when the boat is a charter flight distant). 

Doug, great minds think alike! In fact I discussed this with Gideon who makes the SD50 kits back in 2019 and he thinks it is feasible, but would need a unit to experiment on of course. I have just sent him a a follow up note, to see if he still is interested in investigating, if he can get hold of an existing Kanzaki KM35P gearbox.

If you don't have it the workshop manual for our gearboxes can be downloaded here: www.hughes38.com/wp-content/uploads/2016/02/KM-Series-Service-Manual-incl-KM35P.pdf

Will update this thread when I hear back from Gideon.

Malcolm

PS I have also just sent you a message with an idea...

Ah-hah! Some kind of catalysis going on here. 

I have a KM35P that is a "slipper" and is a cosmetic write-off due to circumstances including a field repair and an unfortunate encounter with spinning, loose flange bolts. Internally it is pristine and I'm sure is perfectly fine as a donor specimen for experimentation. At $1,500 for a rebuild, it's a no-go in that department. 

I was just remarking to my better half that I need to cull the herd of old boat parts. I'd be happy to donate the Kanzaki korpse, ship it if the fees are not too astronomical. Where does Gideon live? 

Thank you for the shop manual pointer! I actually had found the same URL some time ago. I love the part in the manual where it says one can easily slide a particular part onto a particular shaft if the shaft is first dipped in liquid hydrogen (here we always seem to be fresh out of liquid hydrogen). 

[MalcolmP]

Apr 13, 2021 16:01:33 GMT dbostrom said:

Apr 13, 2021 8:48:54 GMT MalcolmP said:

Doug, great minds think alike! In fact I discussed this with Gideon who makes the SD50 kits back in 2019 and he thinks it is feasible, but would need a unit to experiment on of course. I have just sent him a a follow up note, to see if he still is interested in investigating, if he can get hold of an existing Kanzaki KM35P gearbox.

If you don't have it the workshop manual for our gearboxes can be downloaded here: www.hughes38.com/wp-content/uploads/2016/02/KM-Series-Service-Manual-incl-KM35P.pdf

Will update this thread when I hear back from Gideon.

Malcolm

PS I have also just sent you a message with an idea...

Ah-hah! Some kind of catalysis going on here. 

I have a KM35P that is a "slipper" and is a cosmetic write-off due to circumstances including a field repair and an unfortunate encounter with spinning, loose flange bolts. Internally it is pristine and I'm sure is perfectly fine as a donor specimen for experimentation. At $1,500 for a rebuild, it's a no-go in that department. 

I was just remarking to my better half that I need to cull the herd of old boat parts. I'd be happy to donate the Kanzaki korpse, ship it if the fees are not too astronomical. Where does Gideon live? 

Thank you for the shop manual pointer! I actually had found the same URL some time ago. I love the part in the manual where it says one can easily slide a particular part onto a particular shaft if the shaft is first dipped in liquid hydrogen (here we always seem to be fresh out of liquid hydrogen). 

Excellent, Lets make this happen! I have just messaged you and also emailed you with Gideon's details.

[rick63]

Hi,
Just an update on the modification kit fitted to my SD50 cone clutch. Another 200hrs run and no issues so all looking good. Will update again at the end of this season which hopefully will be much better with all Covid lockdown restrictions lifted.

Cheers

Rick

[braders]

Hi 

I’ve just bought an upgrade kit to fit on my SD50, apart from watching the videos and reading how to install the kit do you have any top tips 

Thanks 

Stewart 

[rick63]

Stewart,
My main tip is take your time. The instructions supplied and the videos are very comprehensive. The bit that took longest was setting up the tolerance on the nut when it all bolts together. As per the instructions you need to slowly sand away the face of the nut to suit your clutch assembly. I also assume you have access to a basic workshop as you do need a vice to hold the spline tool to loosen and tighten the top nut. Fitting the adjustable screw and setting it up on the selector assembly is also a bit fiddly but again patience and following the instructions works. Prior to fitting the mod kit I had the clutch out twice to lap it so had a bit of practice on removing it and dismantling it.
If you have any issues give me a shout. Heading of on the 1st June for two months in the boat so might not have regular internet connection.

Cheers

Rick

[braders]

Thanks for the advice Rick - it’s very much appreciated 

Stewart 

[j24sailor]

Nov 7, 2018 12:01:37 GMT srah1953 said:

Hi. I have a 2011 409 with the SD50 Saildrive. I apologise if this seems a stupid question.
How would I know if the cone clutch is slipping? ie, how would it manifest itself? What happens if you ignore it, in long or short term?
Does this problem affect all SD50's, the majority of them or just some?
Thanks for any info you can provide for this ignoramus.

Agree definitely not a stupid question. We have exactly the same boat including the year. This July all of a sudden the boat wouldn't go forwards or backwards. Following several weeks of trying to have it repaired, stumbled across this thread and the repair kit from Gideon and had it installed. Finally repaired last Friday (we are now well into September) and went out this weekend and had no problems.

I am convinced this is the fix but will keep updated. I sent the mechanic the video plus the video from Colin from Below Deck on Sailing Parlay Revival on youtube. Colin's video goes into more detail about the difficult parts of the fix, which convinced us to have someone who knows what they are doing fix it. Apparently the mechanic appreciated Colin's video as well because he is a fan. Thanks James

[NZL50505]

Update on my own SD50 problems.

I had original problem of slipping clutch at 500hrs. After watching the usual videos I engaged the help of a local mechanic and in the space of a morning we removed the clutch assembly cartridge, lapped it, and reassembled. It worked perfectly.

After another 600hrs the problem has repeated. I spoke to my local agent - who is an expert in both auto & marine gearboxes - he said we can repeat the cone lapping of my SD50 which will give me another few 100 hrs but the problem will never go away permanently. He agreed the fix kit from SA is a good option and you can also try other measures like using a graphite infused lubricant to help increase grip between the cones. But he said that the ultimate fix is an upgrade to SD60 which is a relatively straightforward mechanical exercise.

So my plan is to repeat the lapping on my SD50 which will likely give me another 400-500hrs reliable use. But I will plan and budget for upgrading to SD60 before that time expires - which for my relatively high usage will probably be within the next 18 months.

Two other considerations that make upgrade from SD50 to SD60 sensible option for me:

1. My unit is now about 10yrs old so I’m at the point of a new diaphragm - which requires a liftout and removal of my SD50 saildrive anyway. So why not replace with new SD60 at the same time.

2. I’m planning a 6 month cruise to the S Pacific Islands next year and the last thing I want to do is set off knowing that my SD50 will fail again - it’s a matter of when not if. Hence I’d rather bite the bullet and fix that problem permanently before going cruising.

[MalcolmP]

Feb 7, 2024 21:49:32 GMT NZL50505 said:

Hence I’d rather bite the bullet and fix that problem permanently before going cruising.

Sounds very wise NZL.

When you do the change to the SD60, please take lots of photos, so that it can be documented for a future Hints and Tips article. Cheers Malcolm

[NZL50505]

Will be sure to take plenty of pics of other people doing the work (whilst I ‘supervise’) 😊

[MalcolmP]

Feb 8, 2024 0:17:06 GMT NZL50505 said:

Will be sure to take plenty of pics of other people doing the work (whilst I ‘supervise’) 😊

Perfect. Any timescale? Will follow with interest, even though, I have a shaft drive. I have chased Gideon who was planning to make modifications to the Kanzaki gearbox that has the same issues as the SD 50, but no feedback as yet.

Good luck Malcolm

[NZL50505]

I’m travelling in Europe this week but have booked the cone-lapping on my SD50 for Mon 19 Feb as soon as I’m back in NZ. This will give me another few 100 hrs to keep me going rest of the NZ summer season.

Then according to the $ quote from my mechanic, I will schedule the SD60 upgrade - possibly for the NZ winter when things are quieter in the yard and I might get a better labour rate. Which would make it mid-year. That’s current thinking.

[NZL50505]

So I’ve been quoted ~NZD$10,000 for the SD60 unit itself with other parts to make the installation work. Which is about USD$6,200 or GBP5,000 or €5,800.

This excludes labour and local taxes.

Anyone done this before and got a view on:

The reasonableness of the parts prices?

The amount of labour (hrs) typically involved?

I realise I need to add haulout costs to this too.

Boats! 🙄