Twin Disk SP60 Sail Drive Clutch Problems

[JonnyDotNet]

Originally Posted by Eric Jan

Nope but the topic starter has only 20HP if I read that right.

And yes, locking reverse when sailing. Next to the annoying very light rattle the manual says you can't leave it in neutral running with the boat for more than 6 hours anyways.

Yes, that's me. I have 2 x 20HP Beta engines on a 10m catamaran. I used to have 14" Eliche Radice folding props but changed to 15" Autoprops last September. This added over a knot to our motor cruising speed.

[skipperpete]

This is a common enough problem that Maritimus has a cone clutch kit for sale at €1500. These are not good saildrives.

[JonnyDotNet]

Originally Posted by skipperpete

This is a common enough problem that Maritimus has a cone clutch kit for sale at €1500. These are not good saildrives.

Yes, I'm slowly coming to that conclusion. The dilemma is whether to replace like-for-like or change to a Volvo 130. Beta do an adapter plate for these and I can use the same bed but engine mounts have to be changed....

[skipperpete]

Originally Posted by JonnyDotNet

Yes, I'm slowly coming to that conclusion. The dilemma is whether to replace like-for-like or change to a Volvo 130. Beta do an adapter plate for these and I can use the same bed but engine mounts have to be changed....

This is of limited interest to you since you’ve had the SP 60’s on the beds for a while but for first time installation if removing a yanmar saildrive there’s a real problem with the saildrive bed seal to the SP60 diaphragm. The Yanmar diaphragm has a big fat “oring” moulded on the underside of the rubber and in my experience they never leak but the SP 60 has a puny thin sealing edge to keep the ocean out of the engine room. Over time , the yanmar engine bed surface distorts around the hold down bolt holes and the entire area loses its “flat ness”...... not by much, usually by 1 or 2 mm in the dips between the bolt holes but the SP60 is barely able ( or not able) to fill this space with its tiny profile sealing edge. Initially I ground and levelled the saildrive beds with epoxy but eventually used 6 or 8mm alloy capping plates bedded on 5200 (with 2 spacers under the front mounts)to achieve a perfectly flat surface for the SP 60 diaphragms. The SP 60 is not a great saildrive and they make the Yanmar SD50 look pretty darn good, .......at least if you knew about Yanmars problematic cones you could lap em in again while afloat. The shift wedge adjustment mentioned up thread is really grasping at straws, its already spring loaded into the cone vee and prone to seizing the saildrive without moving the bump stop to try and fix a slipping cone although there is a chance if the spring was broken it would be noticeable while doing that adjustment.
To refer to these Technodrive transmissions as “Twindisc” is a an insult to a great American owned and manufactured product that has kept the US commercial and larger motor yacht fleet underway and trouble free for as long as I can remember.... and why they bought into a company like Technodrive is beyond me...... same could be said of Kohler, why they also bought out a company like Lombardini and started rebranding “Lombo’s” as Kohler defies belief too....hopefully these great US companies aren’t just doing this to get products into the EU.

[sailbake]

I have a couple of Twin Disk SP60s in my garage you can have ata very reasonable price. Both had prop seals fail - one has been repaired the other not but the kit comes with it. That was the only problem with them - clutches both good. There is a long history to why I have these, but the short story is BetaMarine supplied the wrong propeller hubs when the installation was new.
I'm in Plymouth UK.

[Icarus]

I had a similar problem with my Twin Disc 60.
They use a cone clutch... Very simple
Check the colour of the ATF.. If black it could be the cone clutch is slipping...
Mine was black so I assumed the clutch was worn... 350Euros from Italy
I took my gearbox apart becouse I thought the clutch cone was worn and slipping.
Anyway, there was no wear so I contacted the manufacturer in Italy.
First
Check and adjust the selector... It is described how to do it in the gearbox repair manual, more or less like a side note, under the reassemble section.
Takes 30 minutes to do. Just a 12mm spanner and a 3mm Allen key from memory.

Check that the gearbox is NOT over filled with ATF fluid... This is important.
Check if the small selector lever clicks in when pushed fw or reverse.
They are very simple gearboxes and easy to work on.
The marine mechanic in Australia wanted 4k to rebuild my gearbox...
The problem with my box was the oil level was 12mm over the top mark on the dip stick and the selector mechanism needed adjusting. Cost 20 bucks for fluid
Also do not whack it into fw or reverse.. Go to neutral for a few seconds first.
Get the repair manual online...

[Goodxcharly]

I think you’re right. Most sail drives are junk and probably a good idea to just go buy a new one. Piece of mind.

[HeinSdL]

Originally Posted by Goodxcharly

I think you’re right. Most sail drives are junk and probably a good idea to just go buy a new one. Piece of mind.

I don't think most saildrives are junk. I have an SD40 with the usual slippage problems, etc, but having studied the thing a bit, fitted Gideon's mod kit, manufactured some special tools, it is easy to maintain and is reliable.

[skipperpete]

Originally Posted by HeinSdL

I don't think most saildrives are junk. I have an SD40 with the usual slippage problems, etc, but having studied the thing a bit, fitted Gideon's mod kit, manufactured some special tools, it is easy to maintain and is reliable.

And even better are the Yanmar SD20-25 saildrives, even treated badly (charter fleets) they last an astonishingly long time, I know of a pair on a cruising cat that have run trouble free for 7,000 hrs attached to 3GM30 engines and for part of their life, spinning Kiwiprops. New prop shaft seals at every haulout and a speedisleeve on each shaft when there were no ungrooved spots left to relocate the seal lips. Even more interestingly the drive plates never showed any major wear or damage despite the dog clutches.

[JonnyDotNet]

Originally Posted by sailbake

I have a couple of Twin Disk SP60s in my garage you can have ata very reasonable price. Both had prop seals fail - one has been repaired the other not but the kit comes with it. That was the only problem with them - clutches both good. There is a long history to why I have these, but the short story is BetaMarine supplied the wrong propeller hubs when the installation was new.
I'm in Plymouth UK.

Thanks for that. I might just take you up on your kind offer. I'm just waiting to see if a fix is going to be a) possible and b) economic. It's interesting that some folk are saying the drive is easy to service and "what's all the fuss about". And some who say it's highly complex and "expensive" so not worth doing. What props do you have on yours?

[JonnyDotNet]

Originally Posted by Icarus

Check and adjust the selector... It is described how to do it in the gearbox repair manual, more or less like a side note, under the reassemble section.
Takes 30 minutes to do. Just a 12mm spanner and a 3mm Allen key from memory.

......

They are very simple gearboxes and easy to work on.
The marine mechanic in Australia wanted 4k to rebuild my gearbox...
The problem with my box was the oil level was 12mm over the top mark on the dip stick and the selector mechanism needed adjusting. Cost 20 bucks for fluid
Also do not whack it into fw or reverse.. Go to neutral for a few seconds first.
Get the repair manual online...

Thanks for the info. My ATF oil is fine. When I enquired about the gear selector adjustment, Beta Marine were pretty dismissive and said it "might" give me a temporary fix "in an emergency" but would not be a lasting solution.

It seems strange to me that the adjustment is made available by the design but is not "recommended" as a fix for clutch slipping by the manufacturer.

I'm down at the boat next week so will give it a try. Thanks.

[skipperpete]

Originally Posted by JonnyDotNet

Thanks for the info. My ATF oil is fine. When I enquired about the gear selector adjustment, Beta Marine were pretty dismissive and said it "might" give me a temporary fix "in an emergency" but would not be a lasting solution.

It seems strange to me that the adjustment is made available by the design but is not "recommended" as a fix for clutch slipping by the manufacturer.

I'm down at the boat next week so will give it a try. Thanks.

The previous poster made a few statements that are confusing, yes, by all means adjust the selector screw and as the previous mechanics suggested I doubt very much if you’ll notice any difference. Screw it in till it bottoms out then back out ¾ of a turn, the adjustment is provided to stop the cone from banging back out after engagement (selector chatter) and a spring actually pushes the selector wedge into the cone vee….. overtightening the adjuster screw and the wedge will seize in the vee and lock up the top gearbox… the pressure provided by the spiral thread is what holds the cone in the cup, not the selector wedge. Apart from the well documented oil blowing out of the breather I don’t quite understand how overfilling the Saildrive can be an important issue, it’s a fairly acceptable procedure to install an elevated little reservoir connected to the vent on the top of the sail-drive to provide positive pressure within the gear case to avoid water getting past a leaking propshaft seal.
In this circumstance there is zero air gap in the gear case (and no chance of oil leaking out of the vent).
These saildrives are actually quite difficult to adjust and setup correctly if the rules are followed( bearing preloads and backlash adjustments) so there’s a damned good reason a mechanic would quote $4,000 to remove and service a SP 60 but if you feel inspired to take a crack at it you can download the illustrated workshop manual from “Varen4U”, Google that and you can see the way it all works and how to fix it. Of interest is that the previous post mentioned only “ black ATF” and selector adjustment, no damage to the cone or selector or even any noticeable slipping, it might have been useful to do an oil change and monitor the oil colour for a few weeks to see if there actually was a slipping cone.

[kitenga]

Originally Posted by JonnyDotNet

OK, Starting a new thread so as not to hijack.

We have 2 x Twin Disk/Technodrive SP60 sail drives mated to Beta 20's on our catamaran. The port drive has just started to slip when going into forward. reverse is fine. I've had various marine engineers look at it and most will not entertain a fix. The suggestion is that I get the unit pulled and fit a new one as it will be uneconomic to fix and any such fix will not be guaranteed to work! So I thought I would check with Twin Disk themselves and they concur. "The unit must be shipped back to us, stripped down and rebuilt".

Now this drive has done around 200 hours and is 2.5 years old. So basically Beta/Twin Disk are saying that the life expectancy of this drive is possibly < 3 years. Moreover, the clutch is not serviceable in-situ and the unit must be pulled and rebuilt.


I'm confused!

Im not confused. I am bitter and upset though. I have a 12.8M cruiser racer with a B50 and SP60. After about 500 hours the clutch failed. After a lot of bitter arguing, and me arguing that the gearbox is not fit for purpose, and threatening legal action, Beta shipped a replacement drive. I paid for the local engineer to replace it, and also the haul out charges. About 5K in total. Beta told me the gear box is only intended for getting in and out of marina, and not for cruising. Clearly the SP60 gearbox is not fit for purpose, and should be taken off the market. Don't forget that iff you have to replace every 2 years at a cost of around 8000 New Zealand dollars, on top of this is the haul out and engineering costs. So every two years rhe maintenance costs on these gearbox is around 10K NZD (Around 5K British pounds)
Twin Disk need to re-design and focus on a quality FOC replacement to all boats.

I feel there is a case for a class action against the manufacturers and I would be prepared to join in on such a class action.

[skipperpete]

Originally Posted by kitenga

Im not confused. I am bitter and upset though. I have a 12.8M cruiser racer with a B50 and SP60. After about 500 hours the clutch failed. After a lot of bitter arguing, and me arguing that the gearbox is not fit for purpose, and threatening legal action, Beta shipped a replacement drive. I paid for the local engineer to replace it, and also the haul out charges. About 5K in total. Beta told me the gear box is only intended for getting in and out of marina, and not for cruising. Clearly the SP60 gearbox is not fit for purpose, and should be taken off the market. Don't forget that iff you have to replace every 2 years at a cost of around 8000 New Zealand dollars, on top of this is the haul out and engineering costs. So every two years rhe maintenance costs on these gearbox is around 10K NZD (Around 5K British pounds)
Twin Disk need to re-design and focus on a quality FOC replacement to all boats.

I feel there is a case for a class action against the manufacturers and I would be prepared to join in on such a class action.

One of the biggest downsides to buying a Betamarine package is the woefully inadequate Technodrive saildrives and gearboxes….to placate us , Betamarine will sell you a bobtail engine with the correct adapter housing to suit a Volvo , Yanmar ,Bukh or possibly ZF Saildrive ( I’m not completely sure re the ZF), the only drawback is that the best saildrive (Yanmar SD25 ) only handles 30 hp so for higher HP engines you’d need to get advice from Betamarine about saildrives other than the shoddy SP60. The Technodrive gearboxes are also very problematic but at least Beta gives us a few really good alternatives to the Italian product.

[sailbake]

The problem with saildrives is the torsional vibration produced by a 3 cylinder diesel engine, exacerbated by the fact that the drive train changes direction twice after it leaves the crankshaft.
If you Google "torsional vibration" you will begin to understand the nature of the problem.

To dampen this torsional vibration you need the correct drive plate in the engine (not the one fitted by Beta) and the correct hub to the propeller (not the one designed for shaft drives).

I have discovered this through bitter experience since 2010 and advice and help from a friend who was an automatic gearbox engineer with AP systems.

This is the reason I have 2 ZF and 2 SP60 saildrives and 2 Brunton hubs sitting in my garage, previously mounted in my FP Fidji 39 with Brunton folding props (with the wrong hubs).

Having eventually understood the cause of the problem and how to resolve it, my latest SP 60s have been operating ok since I fitted them 6 years ago. In fact we have motored back from Vigo with them. Our 3 week holiday between the Scillies, France and Channel Islands last june was mostly motoring, due to lack of wind.

Beta Marine are aware of the issue, because I pestered the life out of them to provide replacement saildrives (which they did) and they helped me get the correct Brunton hubs and drive plates (even though they didn't seem to know much about torsional vibration).

I don't know why they changed from the original ZFs (whose established technology is used all over the world, in military vehicles in particular).

Now I understand the cause of the problem and how to fix it, I would (but for my advanced years now and the need to re-assess the correct drive plates for ZFs) go back to the ZFs whose saildrive gearbox uses wet clutch plates which are easily changed in situ in a day (they did mine 4 times I think - twice afloat), with all parts supplied in a bubble pack kit.

Yesterday I had a conversation with an engineer in the Multihull Centre in Millbrook, Cornwall, who said he was always repairing SP60s and seemed interested in my experience.
If Jonny will get back in contact with me I think I can help him with his current dilemma. I live near the Multihull Centre in SE Cornwall. I am not an engineer, just a persistent enthusiastic sailor who was a TQM advocate in my profession.

Happy to help fellow sailors.