Autohelm ST 4000+ Where to mount fluxgate compass? Rudder ref sensor needed?

Rortega46 · April 16, 2015, 07:33:15 PM

Just purchased a 2001 C34 and love it, but the PO did not take an interest in keeping the instruments functional. Now have the wind, speed and depth instruments working but no such luck with the ST 4000+ wheel pilot. The PO said it never really worked well, so I am guessing something is wrong with the install. The flugate compass is mounted under the sink in the head and appears too close to the engine. Also, there is no rudder referance sensor installed. Question is...does anyone have an ST 4000+ installed that works well? If so, where is the fluxgate compass and do you have a rudder referance sensor installed? Any other suggestions on how to troubleshoot, configure the unit, and get it working will be appreciated.

Roc · April 17, 2015, 04:56:07 AM

I have a 2000 model year and my fluxgate compass was mounted by the factory in the port compartment where the holding tank is located. It is mounted in the most forward area. Autopilot has worked fine since day one. Deviation in that location is only a couple degrees if I remember correctly. The rule for the fluxgate compass is that it should be mounted as low and close to centerline as possible, which is pretty much were mine is.

Exodus · April 17, 2015, 05:12:25 AM

My fluxgate compass is mounted on the bulkhead of the aft cabin pretty much directly below the helm. The rudder reference sensor is optional. I don't have one, but I imagine that it would improve performance.

Jim Hardesty · April 17, 2015, 05:39:57 AM

Congratulations on your new boat. I also have a 2001, great boat, better than I thought it would be. Shamrock has a st4000+ that was installed at the dealer or factory without a rudder ref sensor. Works pretty good I can use it 85% of the time. Originally the fluxgate compass was mounted way aft in the center access under the aft bunk. I moved it to under galley counter forward of the built in-trash can. Worked much better. After reading some here I decided that adding a rudder ref sensor would be an improvement. Bought a new one on ebay. Haven't installed yet. Just uncovered the boat yesterday after a long winter. I don't have any suggestions on troubleshooting, just check the wiring. Configuring the unit is covered in the owner's handbook. If you don't have it, it is on line at the Raymarine website. I find I need to adjust the rudder gain depending on the conditions. May be adding the rps will help that.
For you, try getting it going, but think about spending much on it. Like most electronics, the new ones are better.
Enjoy your new boat.
Jim

Steve_in_lex · April 17, 2015, 07:55:57 AM

Mine's a 2005 and, like Jim, the factory installed fluxgate is way aft. You can see it on the ceiling of the aft cabin but it's pretty far back there. We haven't moved it. I've only had the boat for one season and found that the compass was usually pretty accurate -- within 5 degrees or so -- but every once in a while was quite far off, like 45 degrees. Not sure why...probably something nearby. We don't use the autohelm much -- too many lobster buoys in Maine to take your eyes off the route for any length of time -- but that's a good idea, to move it for more accuracy.

On a separate but related topic, I'm putting in a new MFD and radar, but it's not worth the cost to replace the whole autohelm arrangement, at least not this year. In order for the radar to overlay with the chartmaster, we're putting in a second compass. I'm having the installation done by a pro, and will pass along to him the suggestions in this thread about where to locate it.

Steve

Noah · April 17, 2015, 10:45:10 AM

I have a different system which use a rate compass, but a few general rules of thumb apply on location of fluxgate and/or rate compass: low and centerline, and in an area/locker free of ferrous metal and electronic interference. Not near battery chargers, tool bag storage, etc.

George Bean · April 17, 2015, 11:27:51 AM

Rortega46, what is your hull number? My Year 2000, #1476 boat has the compass mounted on the bulkhead forward of the holding tank. Make sure you are not storing any ferric metals or magnetics (speakers) nearby. We installed a rudder sensor which made a big improvement, but the autohelm will always be a little "wonky". I also dialed down the sensitivity in the control set up. I'll upload a photo of our sensor installation later on.

Rortega46 · April 18, 2015, 06:49:03 AM

Thanks to everyone for the replies and suggestions. My hull # is 1532 and I now know 3 locations for the fluxgate that work, and all better than where mine is now mounted too close to the engine. Based on the amount of cable I can free up, I'll move it to one of the 3 (aft cabin bulkhead, ahead of waste tank, and galley cabinet ahead of trash can).

As far as the rudder referance sensor is concerned, some have one and others don't. It made a big difference on my prior sailboat so I plan to install. If anyone has install instructions please advise. Pictures of your install would be appreciated and a big help as the "professionals" I've talked with say it is a big job.

Noah · April 18, 2015, 10:24:34 AM

I am not familiar with the Autohelm 4000 rudder angle indicator but take a look at my post under the "below deck autopilot" thread to see how I mounted the rudder angle indicatior on my Simrad hydraulic autopilot. It MAY help?

bayates · April 20, 2015, 06:05:44 AM

I have a 2000 sail # 1517 with the 4000 + autopilot and it works great. PO had complete set of spares just in case. The flux gate is mounted in port Setee where east tank is. Factory installed. Would not have boat without "Auto" (it's nickname) working. The trip from San Diego to Catalina is long.

kwaltersmi · April 20, 2015, 07:57:18 AM

I've got the ST4000+ installed on my 87' and have the compass in the after lazarette under the helm seat. I also have the rudder sensor and it seems to work fine. The ST4000+ was a new install during the year before we purchased the boat from the PO, but the PO had it wired backwards and obviously wasn't able to calibrate it. I had the Torresen Marine (original installer) rewire and calibrate and now it seems to work fine. However, the wheel mechanism is noisy!

John Langford · April 23, 2015, 04:11:10 PM

I reduced the noisiness of the wheel drive on my 1999 Autohelm 4000 by washing it out with fresh water and making sure the rod securing the wheel drive to the pedestal fits tightly into the wheel drive. The latter required wrapping the aluminum rod with electrical tape until there was no movement when it was inserted in the wheel drive. Washing the inside of the wheel drive is difficult with the 4000 series because there is no hole designed to accommodate a hose as there is in the 4000+. So I just work the hose around the outside of the drive forcing as much water as I can into the gap between the two parts of the drive. Now there is less rattling noise with every course correction.

However, the 4000 series units are getting old and I anticipate that replacement or serious repair can't be too far in the future. It will be a nightmare running the wires up the very full SS pedestal guards.