myHanse.com - Hanse Yacht Owners Website myHanse.com - Hanse Yacht Owners Website myHanse.com - Hanse Yacht Owners Website myHanse.com - Hanse Yacht Owners Website

Welcome to myHanse.com the forum for Hanse Yachts owners throughout the world.

Forum Home Forum Home > Hints and Tips > 461 / 470
  New Posts New Posts RSS Feed - Auto-pilot clutch slips under load to portside
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Auto-pilot clutch slips under load to portside

 Post Reply Post Reply
Author
Message
psousa View Drop Down
Lieutenant
Lieutenant


Joined: 23 January 2021
Status: Offline
Points: 33
Post Options Post Options   Thanks (0) Thanks(0)   Quote psousa Quote  Post ReplyReply Direct Link To This Post Topic: Auto-pilot clutch slips under load to portside
    Posted: 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?
Back to Top
JonB View Drop Down
Commadore
Commadore
Avatar

Joined: 21 September 2010
Location: Cowes
Status: Offline
Points: 470
Post Options Post Options   Thanks (0) Thanks(0)   Quote JonB Quote  Post ReplyReply Direct Link To This Post 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
Back to Top
psousa View Drop Down
Lieutenant
Lieutenant


Joined: 23 January 2021
Status: Offline
Points: 33
Post Options Post Options   Thanks (0) Thanks(0)   Quote psousa Quote  Post ReplyReply Direct Link To This Post 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.
Back to Top
TheWoods View Drop Down
Sub Lieutenant
Sub Lieutenant


Joined: 04 October 2022
Location: Eastbourne UK
Status: Offline
Points: 1
Post Options Post Options   Thanks (0) Thanks(0)   Quote TheWoods Quote  Post ReplyReply Direct Link To This Post 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....
Back to Top
psousa View Drop Down
Lieutenant
Lieutenant


Joined: 23 January 2021
Status: Offline
Points: 33
Post Options Post Options   Thanks (1) Thanks(1)   Quote psousa Quote  Post ReplyReply Direct Link To This Post 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.
Back to Top
JonB View Drop Down
Commadore
Commadore
Avatar

Joined: 21 September 2010
Location: Cowes
Status: Offline
Points: 470
Post Options Post Options   Thanks (0) Thanks(0)   Quote JonB Quote  Post ReplyReply Direct Link To This Post Posted: 14 October 2022 at 16:49
Did you get a message 'drive stopped'?
Jon B
470e
http://www.norse-king.blogspot.co.uk
Back to Top
psousa View Drop Down
Lieutenant
Lieutenant


Joined: 23 January 2021
Status: Offline
Points: 33
Post Options Post Options   Thanks (0) Thanks(0)   Quote psousa Quote  Post ReplyReply Direct Link To This Post Posted: Yesterday 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 - Yesterday at 10:23
Back to Top
Wild View Drop Down
Rear Admiral
Rear Admiral
Avatar

Joined: 18 March 2010
Location: Turkey-Greece
Status: Offline
Points: 604
Post Options Post Options   Thanks (0) Thanks(0)   Quote Wild Quote  Post ReplyReply Direct Link To This Post Posted: Yesterday at 16:58
Originally posted by psousa<div>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</div>[/QUOTE psousa
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
[/QUOTE wrote:


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
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 - Yesterday at 17:02
Wild and Wet
Belgium
545e#268
Back to Top
psousa View Drop Down
Lieutenant
Lieutenant


Joined: 23 January 2021
Status: Offline
Points: 33
Post Options Post Options   Thanks (0) Thanks(0)   Quote psousa Quote  Post ReplyReply Direct Link To This Post Posted: 9 hours 2 minutes ago at 09:32
Originally posted by Wild Wild wrote:

Originally posted by psousa<div>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</div></td></tr></table><div>This looks normal to me.</div><div> 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.</div><div>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.</div>[/QUOTE psousa
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
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.
[/QUOTE wrote:


Not to me, Wild. In this video I was holding the wheel with one single finger, pressed 10 degrees starboard button and it fails like this. Also fails if autopilot is on and I steer portside with one single finger. Not normal at all.

This all starts at the beginning of last season, when the autopilot started failing to keep the head when close hauled or reaching over 15knots of wind and light swell. With this conditions I could be sleeping on any of my previous smaller sailing boats. These are quite light conditions for a 47 boat and a strong autopilot unit drive like this and that's why I start talking to Jefa Steering Systems one year ago. They agreed it wasn't normal and even suggest to send the driver unit so they can inspect it. I only identify this issue now, while going through the

Not to me, Wild. In this video I was holding the wheel with one single finger, pressed 10 degrees starboard button and it fails like this. Also fails if autopilot is on and I steer portside with one single finger. Not normal at all.

This all starts at the beginning of last season, when the autopilot started failing to keep the head when close hauled or reaching over 15knots of wind and light swell. With this conditions I could be sleeping on any of my previous smaller sailing boats. These are quite light conditions for a 47 boat and a strong autopilot unit drive like this and that's why I start talking to Jefa Steering Systems one year ago. They agreed it wasn't normal and even suggest to send the driver unit so they can inspect it. I only identify this issue now, while going through the winter maintenance list.

This is a 150nm sprocket drive, so it should be able to handle forces which are quite demanding for humans to keep. The whole system should be able to handle these conditions as well. You can see the graphics here: https://www.jefa.com/steering/products/drives/sprocket-150nm.htm

I emailed again to Jefa with this update as I just want to understand if the culprit may be the sprocket failing. I don't know if this is something we should replace time to time.

Back to Top
Wild View Drop Down
Rear Admiral
Rear Admiral
Avatar

Joined: 18 March 2010
Location: Turkey-Greece
Status: Offline
Points: 604
Post Options Post Options   Thanks (0) Thanks(0)   Quote Wild Quote  Post ReplyReply Direct Link To This Post Posted: 7 hours 44 minutes ago at 10:50
Sorry 
In your previous posts you write “holding the wheel with my hand” 💪
You didn’t mention “with one finger”☝️
I my 12 year experience with the same Jefa steering system (545= same as 470) when the wheel can’t move freely in AP mode I have that issue.
Wild and Wet
Belgium
545e#268
Back to Top
 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.01
Copyright ©2001-2018 Web Wiz Ltd.

This page was generated in 0.063 seconds.

Links : www.hanseyachts.co.uk www.hanseyachts.com www.fjordboats.co.uk www.dehler.co.uk www.varianta.co.uk