Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 31-07-2009, 07:25   #1
Registered User
 
ixtlan22's Avatar

Join Date: Dec 2007
Location: Currently liveaboard -Ensenada
Boat: Catalina 30
Posts: 87
Autopilot Question

We are getting ready to go cruising.

We have an older model Raymarine Autohelm 6000.

On the shakedown cruise, we discovered that the autopilot is not working correctly as, when we engage the unit, the boat tends to go starboard in a circle and will continue to do so regardless of any attempts at resetting or adjustment. It's important to note that the unit has been on the boat for several years and will engage and dis-engage when activated... it's just that when it does engage it only goes right....in a circle. I do not know if it's always been like this as this is our first test of this system.

Looking up in Nigel's book "Boatowner's Mechanical and Electrical Manual," it states that this problem is probably due to interference from the alternator.

We are puzzled because the control head, fluxgate compass, computer, and linear drive are all located well away from the alternator and each have their own circuit. Anyone have any ideas about what's causing this or methods of resolution?

BTW we have a spare fluxgate compass and computer onboard but have not wanted to try them until we get more ideas...especially about the alternator and if it's actually the culprit.

Ray
__________________

__________________
ixtlan22 is offline   Reply With Quote
Old 31-07-2009, 07:30   #2
Registered User
 
Eleven's Avatar

Join Date: Sep 2007
Location: Southampton UK
Boat: Jaguar 22 mono called Arfur.
Posts: 1,220
Images: 3
I have the manuals for the AutoHelm 4000 on my boat which does similar. If the play in the helm is greater than 20 deg the auto cant cope. Mine has sisty deg play and it doesn't cope.
Damn nuisance when trying to navigate, trim, make coffee, etc. Need two in the cockpit at the moment. Good luck.
__________________

__________________
Ex Prout 31 Sailor, Now it's a 22ft Jaguar called 'Arfur' here in sunny Southampton, UK.
A few places left in Quayside Marina and Kemps Marina.
Eleven is offline   Reply With Quote
Old 31-07-2009, 08:10   #3
Senior Cruiser
 
JusDreaming's Avatar

Cruisers Forum Supporter

Join Date: Jul 2004
Location: Stuart, FL & Bahamas Cruising
Boat: Lagoon 37
Posts: 880
Images: 13
Our's did that and I ended up calling Raymarine tech guys and they talked me through a fix for it!! Unfortunately I have "CRS" and don't remember what they had me do
__________________
Denny and Diane
Lagoon 37
http://www.svjusdreaming.bravehost.com/
http://www.sailblogs.com/member/svjusdreaming/
"The only way to get a good crew is to marry one." -Eric Hiscock
JusDreaming is offline   Reply With Quote
Old 31-07-2009, 08:15   #4
Moderator Emeritus
 
Pblais's Avatar

Join Date: Mar 2003
Location: Hayes, VA
Boat: Gozzard 36
Posts: 8,700
Images: 15
Send a message via Skype™ to Pblais
You need to start with the basics. You need rudder feedback and fluxgate compass data. Does the compass change as you move the boat. Is it accurate at least to each of the 90 degrees? Does the rudder feedback display properly. If either of these are bad then you'll get that result. The next idea would be the course computer (the expensive part). You can check the rudder feedback with a multimeter. The rudder feedback is like the volume control on a stereo. It sends out a reference voltage and gets back a reading. There is a calibration for center and the computer does the rest. You can measure the return voltage where it connects to the computer.

To test the compass unmount it from it's location and slowly rotate it and read the display on the control head. The compass works in 4 quadrants of the compass so testing the transition between them is what you need to validate. If the compass passes mounted then it should be fine and not require testing unmounted. It is possible something steel is now too close where it didn't used to be close. It happens a lot and folks are sure nothing changed. Someone put something away where it didn't used to be and thinks nothing of it.

If you can validate the reading on the control head then you know these two are not the problem. Pray for a bad rudder feedback - they are the cheapest. The compass is only a tad more. The control head would be next at about triple the compass.

I've been down this road twice on two different boats. You need to eliminate what is not a problem then zero in on the rest. With simple tools and thinking it through it is possible to troubleshoot this.
__________________
Paul Blais
s/v Bright Eyes Gozzard 36
37 15.7 N 76 28.9 W
Pblais is offline   Reply With Quote
Old 31-07-2009, 08:45   #5
Registered User
 
ixtlan22's Avatar

Join Date: Dec 2007
Location: Currently liveaboard -Ensenada
Boat: Catalina 30
Posts: 87
Thanks Paul,

Sounds like good directions to get started. Like I said, I do have a spare fluxgate and spare computer so I'm sure I'll get something to work. Like all diagnostics it sounds like it's just a process of elimination.

Haven't noticed anything new around the compass or computer but I'll look a little closer.

Ray
__________________
ixtlan22 is offline   Reply With Quote
Old 31-07-2009, 12:01   #6
Registered User

Join Date: Apr 2009
Location: Marina Del Rey
Boat: Hylas 44
Posts: 387
We had a similar problem when we took delivery of our boat. The previous owners were never able to get the autopilot to work.

The problem was that the wires to the drive unit were reversed.

Chuck
__________________
ChuckSK is offline   Reply With Quote
Old 01-08-2009, 04:31   #7
Registered User

Join Date: May 2009
Location: NJ, Paris FR and, for the moment, Cape Coral FL
Boat: Islander Freeport 41, AEGEA
Posts: 186
First try to use it without the engine running. That will answer the alternator question in short order. If that's OK I agree with the reversed wire scenario.

Dick Pluta
AEGEA
__________________
Dick Pluta is offline   Reply With Quote
Old 01-08-2009, 05:20   #8
Don't ask if you can't handle it
 
sailorboy1's Avatar

Cruisers Forum Supporter

Join Date: Jul 2007
Location: On the boat somewhere
Boat: Hunter 410
Posts: 12,320
I had that problem onceand it was becaquse the clutch wasn't fully engaged.
__________________
sailorboy1 is online now   Reply With Quote
Old 01-08-2009, 05:44   #9
Eternal Member
 
Chief Engineer's Avatar

Join Date: Aug 2006
Location: North of Baltimore
Boat: Ericson 27 & 18' Herrmann Catboat
Posts: 3,798
TRy resetting the unit.
__________________
Chief Engineer is offline   Reply With Quote
Old 01-08-2009, 09:22   #10
Senior Cruiser
 
nautical62's Avatar

Cruisers Forum Supporter

Join Date: Jul 2008
Location: Live Iowa - Sail mostly Bahamas
Boat: Beneteau 32.5
Posts: 2,264
Images: 12
This seems to be a common problem. I'm having the same issue in setting mine up for the first time. The compass reading is fairly accurate at all points. The rudder gain is about 13, but when I turn on the learning mode, it goes into increasingly tight circles to port. Very frustrating.
__________________
nautical62 is offline   Reply With Quote
Old 01-08-2009, 09:25   #11
Eternal Member
 
Chief Engineer's Avatar

Join Date: Aug 2006
Location: North of Baltimore
Boat: Ericson 27 & 18' Herrmann Catboat
Posts: 3,798
I have had to recalibrate mine at the beginning of each season.
__________________
Chief Engineer is offline   Reply With Quote
Old 01-08-2009, 10:45   #12
Moderator Emeritus
 
Pblais's Avatar

Join Date: Mar 2003
Location: Hayes, VA
Boat: Gozzard 36
Posts: 8,700
Images: 15
Send a message via Skype™ to Pblais
Quote:
The compass reading is fairly accurate at all points. The rudder gain is about 13, but when I turn on the learning mode, it goes into increasingly tight circles to port.
Having no rudder feedback signal at the computer will causes this. When the computer can't find a rudder signal it increases the rudder applied until can't apply any more. The rudder sensor is required for any operation to work. It does not really know where the rudder is unless gets signal. No signal forces it hard over and it ignores the compass data. Not being calibrated won't cause this as the rudder feedback will work but it won't have a perfect idea of where the center position is when uncalibrated. It will be able to guess so long as there is a signal. It already knows the nominal voltage range the rudder feedback can send. Voltage drop and other minor issues will come out through calibration. Calibration will store the voltage reading for the center position as well as mark the range of the rudder adjustment.

Similarly the compass will transmit a signal but it won't have the on board deviation computed until you do the circles calibration. It will basically work with no calibration just not as good as it will after. The compass calibration builds a deviation card inside the computer for every degree of heading and saves it. This should make the fluxgate readings pretty good.

The manual settings are more for the dynamics of the hull and engine and in calm water should not effect the use. At higher speeds and rough weather the settings do make the boat steer stable when adjusted assuming the power is there to control the rudder. Undersized auto pilots can't be adjusted to have more power that they have.
__________________
Paul Blais
s/v Bright Eyes Gozzard 36
37 15.7 N 76 28.9 W
Pblais is offline   Reply With Quote
Old 01-08-2009, 11:31   #13
Senior Cruiser
 
nautical62's Avatar

Cruisers Forum Supporter

Join Date: Jul 2008
Location: Live Iowa - Sail mostly Bahamas
Boat: Beneteau 32.5
Posts: 2,264
Images: 12
So why doesn't it get the rudder signal and how is that corrected? I did the circles thing and that's when I got the reading of 13 I think it was. It was within what the manual said was acceptable.
__________________
nautical62 is offline   Reply With Quote
Old 03-08-2009, 10:59   #14
Registered User
 
scotte's Avatar

Join Date: Apr 2007
Location: SF Bay Area, CA, USA
Boat: Privilege 39
Posts: 664
nautical62, does your display head have a rudder angle indicator? If so, see if it is showing reasonable rudder angles as you move the wheel lock to lock.

Don't worry about the gain setting at this point - start by determining if the A/P is getting all the data it needs, as that is a prerequisite to worrying about calibration.
__________________
scotte is offline   Reply With Quote
Old 03-08-2009, 11:09   #15
Registered User

Join Date: Apr 2009
Location: Marina Del Rey
Boat: Hylas 44
Posts: 387
The Autohelm 6000 does not have rudder feedback.
__________________

__________________
ChuckSK is offline   Reply With Quote
Reply

Tags
autopilot

Thread Tools
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
Autopilot question captain465 Monohull Sailboats 17 09-04-2014 18:04
Autopilot? surfingminniwinni Deck hardware: Rigging, Sails & Hoisting 0 18-03-2008 01:03
autopilot Red Horse Multihull Sailboats 4 26-01-2008 10:35
Which Autopilot?????????????? avazquez Marine Electronics 21 30-09-2007 22:35
Autopilot salty Marine Electronics 3 25-03-2004 17:48



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 15:05.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.