We have a Raymarine 4000 Autopilot that has slipped out of sync with our nav compass to the tune of about 20 degrees. I have read the Raymarine material regarding re-calibrating the 4000 by driving the boat in large circles, etc. Does this process work? If not, has anyone found an easier/better way to recalibrate?
Auto pilot compass re-calibration...
- Thread starter Doug/Karen
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Yes it does work is the short answer.
The first thing I would check is that someone has not place some large metal item near the Raymarine Flux-gate Compass. If that hasn't happened just follow the instructions that came with the ST4000. The circles do not have to be that big. 50 to 100 yards radius will do it.
How does the ST4000 line up in regard to the Chart Plotters COG?
The first thing I would check is that someone has not place some large metal item near the Raymarine Flux-gate Compass. If that hasn't happened just follow the instructions that came with the ST4000. The circles do not have to be that big. 50 to 100 yards radius will do it.
How does the ST4000 line up in regard to the Chart Plotters COG?
make sure your GPS is up
and connected to the SeaTalk buss BEFORE you begin alignment
OR
know your magnetic deviation
it should ask you so it can calculate the true course for the display
and connected to the SeaTalk buss BEFORE you begin alignment
OR
know your magnetic deviation
it should ask you so it can calculate the true course for the display
I've been trying to re-calibrate mine. I did not have the manual. I did however have the quick chart instructions. I followed the instructions on the quick chart and it did not work.
I posed the question why it wouldn't work here a few months ago and got a reply that there are new updated instructions on the web.
I printed them out, (all 135 pages), and had them bound at Kinko's. Gonna try again this weekend.
You might want to check for new instructions on the web.
I posed the question why it wouldn't work here a few months ago and got a reply that there are new updated instructions on the web.
I printed them out, (all 135 pages), and had them bound at Kinko's. Gonna try again this weekend.
You might want to check for new instructions on the web.
Right: check the magnetic
First eliminate the possibility that your magnetic compass is off. This can happen not just if an iron object is placed next to the fluxgate compass unit (which is under the aft bunk access ports, and mounted on the aft bulkhead in your 356), but can also happen if any magnetic material is placed anywhere within about 6 feet from the steering pedestal. This includes smaller items that can become magnetized, such as non-aluminum beer or soft drink cans, screwdrivers, containers, or any other items that contain iron.
Once you have determined that that is not the case then sail the boat in a known magnetic direction aiming for a fixed landmark according to an official chart, and see what the compass reads. Repeat for each of the cardinal directions. If your magnetic compass still reads more than a few degrees off the true magnetic direction you have to "swing" the compass and adjust is two compensation magnets (with a brass screwdriver), but it would be a clear indicator that your autopilot compass is not the culprit.
Only after this is done should you attempt to correct your autopilot compass.
Good luck.
First eliminate the possibility that your magnetic compass is off. This can happen not just if an iron object is placed next to the fluxgate compass unit (which is under the aft bunk access ports, and mounted on the aft bulkhead in your 356), but can also happen if any magnetic material is placed anywhere within about 6 feet from the steering pedestal. This includes smaller items that can become magnetized, such as non-aluminum beer or soft drink cans, screwdrivers, containers, or any other items that contain iron.
Once you have determined that that is not the case then sail the boat in a known magnetic direction aiming for a fixed landmark according to an official chart, and see what the compass reads. Repeat for each of the cardinal directions. If your magnetic compass still reads more than a few degrees off the true magnetic direction you have to "swing" the compass and adjust is two compensation magnets (with a brass screwdriver), but it would be a clear indicator that your autopilot compass is not the culprit.
Only after this is done should you attempt to correct your autopilot compass.
Good luck.
Folding cushion effect...
We discovered that placing one of those metal-framed folding cockpit cushions on the same side of the aft cockpit seat of our H34 would cause our former 4000 autopilot mounted on that side to want to vear to the right once engaged. Keeping the cushion (and the Admiral) on the other side of the cockpit solved the problem.
We discovered that placing one of those metal-framed folding cockpit cushions on the same side of the aft cockpit seat of our H34 would cause our former 4000 autopilot mounted on that side to want to vear to the right once engaged. Keeping the cushion (and the Admiral) on the other side of the cockpit solved the problem.
What affects the Flux gate may or may not affect the magnetic compass.
It really doesn't make any difference if your magnetic compass is correct or not as far as the autopilot is concerned. Now don't jump off the deep end, I didn't say that your magnetic should not be correct but they are two different and separate problems to be solved independent of each other.
Also swinging the autopilot compass seems to always take two people. One to read the instructions out load and another to press the buttons and drive the boat as instructed.
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Make sure to read the whole autopilot setup instruction section. I haven't had an ST4000 in a number of years, but seem to remember the first step being to set the gross error difference between compass and autopilot using an unremembered set of keystrokes and then the +1 -1 keys to get the two compasses much closer than 20 degrees off. Then, you do the calibration drive the boat in circles maneuver. I fear that starting more than 20 degrees off is far to large an error for the fine calibration maneuver to overcome.
I've done the compass swing this year. It isn't overly hard. I entered my latitude and started the swing. It did take 2 or more circles to finish the calibration but patients is the key. After that the autopilot worked great. I had replaced the wind computer module requiring the mast head to be swung also. My system has a 400G course computer and fluxgate compass. Not sure if the 20+ degrees of deviation will effect the calibration, but as another said, the magnetic compass has no bearing on how the autopilot system gets its information. The system should start fresh when you calibrate and come up with variation and deviation corrections and if your magnetic compass is correct, they should be very close.
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