Autohelm 4000 problem

PhilipStapleton

Well-Known Member
Joined
10 Jul 2001
Messages
192
Location
Berkshire
www.radartutor.com
After 6 years my Autohelm 4000 (wheel) autopilot started giving problems. Sometimes it jumped out of engagement (mainly lifting the lever itself when turning to port), and sometimes it jammed when not engaged. I got it "repaired" at enormous expense, but 1 year and 20 hours use later the problem’s back.

The manual doesn't show how to get inside, and there are no obvious screws to undo. Does anyone have a similar experience and - preferably - a fix?
 
Had the same problem as you which turned out to be a worn drive belt. As I remember the thing "clicks" open. They are available from Bearing Services a lot cheaper than Autohelm.

Cheers

John Dillon
 
I have 4 year old 4000+ wheel autopilot and just a few weeks ago it started winding back the clutch lever and disengaging itself - most annoying and at times rather critical. If yours is the same, which I believe it is, remove wheel from pedestal and place flat on deck. Tap out the roll pin ( I use a 1mm drillbit as a drift) which secures the clutch lever to the ss axle of the clutch mechanism. Slide the lever off the axle.
The two parts of the autopilot do just spring apart - some gentle help from a large screwdriver needed.
I replaced the belt for a new one which helped a lot, but it still ocassionally disengaged itself. I then carefully cleaned the clutch mechanism, which is essentially an offset cam with an overcentre action, and lightly greased with silicon grease. Again this has helped but has not totally solved the problem.
Apart from ensuring there is no build up of salt deposits around the pulleys I am now at a loss as to what to try next but this might help yours.
Reassembly - a firm push will clip the back plate onto the autopilot. Just make sure the drive belt is clear of the housing.

Hope this helps.
 
There is a tensioner adjusted with an Allen key (I think) on the back of the section that attaches to the wheel. It has a black plastic blank covering it's head which you must remove. We suffer the same problem and I have yet to make this adjustment but have it on good authority that this will stop the self-disengagement.
 
Have you tried the Raymarine web site? They have a pretty good support service (free) that I've used successfully in the past. If this is a common problem, then chances are there'll be a solution posted on the site. If not they'll take on-line questions and, unlike too many sites, you'll actually get a sensible reply.

Try it at http://www.raymarine.com/recreational/support/index.html
 
The toothed wheel....

... which fits into the lever is your problem. Take the lever out and try different positions of the wheel relative to the lever arm. This is how the lever position is moved to accomodate your particular installation and also allows for stretching of a new belt to be taken up. Tension is applied by the eccentric hole in the little toothed wheel (cog) for the pin pulling the motor unit back against the belt when the lever is rotated. It is at it's most "stable" position when the hole is right back & therefore exactly in line with the drive pulley & steering wheel centres. Anywhere else and it will eventually free itself on one turn or the other. If your belt gets too tight in this position then you will need to move the drive unit inwards a little until it is acceptable.

We fiddled with ours for 800 miles and eventually got it right. Trouble is that the occassional charterer will insist on "knowing better" (or maybe just fiddling!) and changing it.

Steve Cronin
 
I had the same problem and had a new belt fitted but this didn't cure it. The answer was to open it up myself and fit a Raytheon No11 4000M clutch lever and a No24 clutch eccentric assembly at a cost of about £20. This was on the advice of raytheon and it did the job although I couldn't see how it would before hand. Hope this helps.
 
I've adjusted the tensioner until it is in the minimum tension position by turning the allen key (which is tiny, 1.5mm from memory) but to tighten in any other position you seen to need a 'special tool' with two projecting pins to hold the nut that locks the allen key. Anyone find a way of doing this?
 
Re: The toothed wheel....

I think you are referring to the 4000WP and not the 4000+ which has an integral drive and enclosed belt??
 
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