|
| |
| Welcome to myHanse.com the forum for Hanse Yachts owners throughout the world. | |
Auto-pilot clutch slips under load to portside |
Post Reply 
|
| Author | |
psousa 
Lieutenant 
Joined: 23 January 2021 Status: Offline Points: 32 |
 Post Options
 Thanks(0)
 Quote Reply
 Topic: Auto-pilot clutch slips under load to portsidePosted: 31 January 2022 at 17:24 |
|
Hi there!
My Jefa autopilot clutch fails when I pull the rudder wheel to port with my hands while the autopilot is engaged. It slips. Before this manual test, I realise this failure few times already when sailing close haul with 15/16 knots winds. The pressure over the rudder increase and the clutch starts failing. The system keeps trying to lock the rudder and eventually do it again when the boat gets into the wind, obviously reducing the pressure over the rudder. This happens only to one side. To the other one the clutch holds pretty well. Contacted Jefa and they ask me to do a test: to connect the clutch directly to the battery and try to pull the wheel by hand. Obviously they are trying to exclude the simrad autopilot computer from the equation, but before doing it I would like to ask you guys if you ever had such a problem and what are your thoughts about it. Is it possible to be an autopilot computer issue? Isn't the clutch a on/off only feature?
|
|
 |
|
|
JonB
Commadore 
Joined: 21 September 2010 Location: Cowes Status: Offline Points: 470 |
Post Options
Thanks(0)
Quote Reply
Posted: 01 February 2022 at 22:08 |
|
Hi,
My old Raymarine auto pilot had Alzheimer's in that it would suddenly let go with 'no drive' warning, I took the motor off to test the clutch, all good and yes its either engaged with pins or its not, so it can't slip. Thinking that it may be an issue between the fluxgate and the compass within the unit I tested the fluxgate. Deciding I didn't really know whether my findings would tell me anything I could understand and having upgraded the E series plotters to Axioms I opted to replace the auto too. The ACU 200 was fitted and off I went only for it to fishtail the boat until we nearly gybed. I undertook several tests and once again it opted to, under engine (little wind), follow a search pattern without being asked to. It was a struggle to get Raymarine to accept anything other than a limpware (user) issue, but eventually they sent over an Engineer who came and inspected with the Engineer who fitted it. When the auto pilot was asked to steer +10degrees and the helm was held to simulate weather helm, they were surprised that 15amps was called for by the Jeffa motor, bearing in mind it is protected with a 40amp fuse. They've since changed the unit for an ACU 400 which I assume handles the amperage better and once installed and the boats back in the water we'll be testing again. Check the rudder sensor, probably by disconnecting it and see if it's the same both sides or cures the problem. You could have a similar issue in that the amperage being asked by the motor exceeds that of the unit fitted.
|
|
|
Jon B
470e http://www.norse-king.blogspot.co.uk |
|
|
|
|
psousa
Lieutenant
Joined: 23 January 2021 Status: Offline Points: 32 |
Post Options
Thanks(0)
Quote Reply
Posted: 03 February 2022 at 11:14 |
|
Interesting...
Regarding the amp demand for Jefa 12v sprocket drive unit (I guess the one you have), there is a graph which clearly shows it can demand up to 16amps when under weather conditions: https://www.jefa.com/steering/products/drives/sprocket-150nm.htm My boat is equipped with a simrad ac42 autopilot computer. According to the manual, it can supply: AC42: ....................30 A continuous, 50 A for 1 sec. peak More, the issue is happening when pushing the wheel to portside only (doesn't happen when pushing the wheel to SB), so I guess it's not a power delivery issue. I'll give a closer look ate compass and the rudder feedback when back to the boat.
|
|
|
|
|
TheWoods
Sub Lieutenant 
Joined: 04 October 2022 Location: Eastbourne UK Status: Offline Points: 1 |
Post Options
Thanks(0)
Quote Reply
Posted: 04 October 2022 at 16:06 |
|
psousa - did you find a solution to this question? I had exactly the same symptoms on my 430 this summer and looking to solve the problem as well. Thanks
|
|
|
Red sky at night....
|
|
|
|
|
psousa
Lieutenant
Joined: 23 January 2021 Status: Offline Points: 32 |
Post Options
Thanks(1)
Quote Reply
Posted: 14 October 2022 at 15:40 |
|
nope! I was in touch with Jeffa and they sent me a PDF with instructions to test the drive unit/clutch. The issues happens even when bypassing the computer unit, so it seems to be a drive issue, we believe. They suggest to send the drive unit back to Jeffa in order to be serviced by them, in Denmark, which I didn't.
I'm living with it. I keep close to the wheel when winds get stronger. But eventually I would need to look at this and fix it. Please keep us updated with further steps you decide.
|
|
|
|
|
JonB
Commadore
Joined: 21 September 2010 Location: Cowes Status: Offline Points: 470 |
Post Options
Thanks(0)
Quote Reply
Posted: 14 October 2022 at 16:49 |
|
Did you get a message 'drive stopped'?
|
|
|
Jon B
470e http://www.norse-king.blogspot.co.uk |
|
|
|
|
psousa
Lieutenant
Joined: 23 January 2021 Status: Offline Points: 32 |
Post Options
Thanks(0)
Quote Reply
Posted: 15 hours 1 minutes ago at 10:19 |
|
No, never got that message but I found the issue: the steering chain/cable has a considerable slack and, under certain tension, the chain slips on the autopilot sprocket wheel. Just gave tension on the steel cable nuts close to the quadrant. On a quick test at the marina, with my hands, couldn't make it slip anymore. I'll check again at the sea (need some rough conditions and winds to test it again).
On this video you can see the autopilot trying to turn while I was holding the wheel with my hand which results on a slips chain/sprocket wheel: https://mega.nz/file/5xJRURLD#n9VKAVmGdLEbey9Z1Zi8FbwX-bk8DVtXA2DYntjX7Kw Edited by psousa - 14 hours 57 minutes ago at 10:23 |
|
|
|
|
Wild
Rear Admiral 
Joined: 18 March 2010 Location: Turkey-Greece Status: Offline Points: 603 |
Post Options
Thanks(0)
Quote Reply
Posted: 8 hours 22 minutes ago at 16:58 |
This looks normal to me. moored in the marina with the AP in AUT mode the boat move a bit and the AP will correct this small movements. when you block the wheel by hand this result in the drive unit will turn a bit to left and right and the chain jumps up and down on the sprocket of the drive unit. If you take all the slack of the cables and keep the wheel blocked for a longer period the AP control unit will give first the alarm code NO RUDDER RESPONSE and finally DRIVE OVERLOAD. When the slack of one of the cables is to big the chain will finally jump of the sprocket our the cable will jump of the rudder quadrant.
Edited by Wild - 8 hours 18 minutes ago at 17:02 |
|
|
Wild and Wet
Belgium 545e#268 |
|
|
|
|
Post Reply
|
|
Tweet
|
| Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |
|
Links : www.hanseyachts.co.uk www.hanseyachts.com www.fjordboats.co.uk www.dehler.co.uk www.varianta.co.uk |
Topic Options
psousa