Autohelm 6000 has become unreliable

[smb]

In the 13 years we have owned our yacht the ancient Autohelm 6000 has performed faultlessly, holding a steady course irrespective of weather, sea state and less than optimum sail balance. Last summer however it started to occasionally play up.

We might be motoring along in a dead calm with the pilot holding course when for no reason we veer off, normally (maybe even exclusively) to starboard. Sometimes just a matter of 30 deg or so, othertimes hard over to the stops.

Whilst this happens the course display is still showing the set course. This remains the case even after disengaging the pilot and either returning to the desired course or indeed motoring in a circle, then at variable intervals later and with no input from us the course display will correct and we can re-engage the pilot and continue on our merry way.

I would like to know if anyone has had this issue and resolved it, or any suggestions as to possible cause.

Regards

Steve

 

[ChrisE]

Have you looked at the wiring to the control box? I had similar probs when ours was first installed and traced it back to a loose wire.

 

[Neil_Y]

I'd be looking for corrosion and loose connections in all connectors boxes and boards, I also had an old 6000 that worked great, but during preparation for a transat I found a number of connectors suffering from salt/moisture, easily sorted with ACF-50 and cleaning up wire ends. It never failed or went off course but the display was giving strange numbers.

 

[Ric]

Does your control head have its own dedicated power supply? Or is it taking its power from the seatalk network?

 

[smb]

Thanks for the replies.

I initially suspected a problem with the compass or the wiring between it and the main box, so removed cleaned (no obvious tarnish or corrosion) and replaced those wires. Visually the other connections in the box looked ok but it cant do any harm to give them the same treatment. Iirc wiring at the control head is by way of a moulded fly lead so no opportunity for the same treatment there.

Steve

 

[smb]

Does your control head have its own dedicated power supply? Or is it taking its power from the seatalk network?

The 6000 I have predates seatalk. It only has one connection to the control head, the one from the course computer.

I think there was subsequently an Autohelm 6000ST

Steve

 

[Billjratt]

I have the same device...Agree you should investigate connections at computer interface blocks and check for cable chaffing/integrity.
Looks like it issues a helm command and doesn't get a course alteration indication from the fluxgate so it just waits for one...
Also consider any changes or new equipment that may cause interference or power issues.

 

[pvb]

Whilst this happens the course display is still showing the set course. This remains the case even after disengaging the pilot and either returning to the desired course or indeed motoring in a circle, then at variable intervals later and with no input from us the course display will correct and we can re-engage the pilot and continue on our merry way.

This makes it sound like a course computer or control head problem, rather than a fluxgate problem. It would be worth asking a couple of companies who repair these if it's a fault they recognise.

Alternatively, you could see whether anyone has a spare course computer you can borrow to test whether that cures it. I might even have one myself somewhere, depending on the precise model.

 

[smb]

Belated thanks for the replies. When I get back to the boat in a few weeks time I will again clean all the connections. I found a manual online that that suggests the course computer seperates from the I/O unit, so there must be a host of connections there that could be less than perfect. I will also be equiped to replace the cable connecting the fluxgate. There is a slight possiblilty that the original has been damaged as it shares a hole through a bulkhead with a holding tank outlet pipe which pulses when the tank is being pumped to sea.

Steve

 

[smb]

Just as a footnote and in case anyone else searches on the same problem, I have resolved this issue.

The fault was caused by 25 year old dry solder joints where the 25 pin D connector is soldered to the interface board, sods law dictating it was the pins that the fluxgate feeds through that were faulty, not the 15 or so redundant ones.

Application of a hot iron soon fixed that, and we're back to relaxed cruising, if only the weather would play ball.


Thanks again for the responses.

Steve