Autohelm ST4000 always going to the right.

[Sleek Geek]

Autohelm ST4000, Wheeldrive Autopilot. Worked great until yesterday. Push standby button, Engage drive lever, and push autopilot button. Wheel jumps back and forth as usual but, it will only make a course adjustment to the right and not to the left? As a result my boats sails the right and does not maintain the punched in coarse? Any ideas, I am a very long trip and get really tired being at the helm all day while cruising?

[CaptainDan99]

Check all of the connections to the fluxgate compass. Make sure they are tight and clean.

Is this a ST4000 or a ST4000 Plus? What happens if you push the -10 button in auto. Does the wheel turn to port?

[deniseO30]

Do you have a cell phone in your pocket? I discovered that I could "steer" the AH with my cell phone's magnetic field or whatever it is they produce.

[jrd22]

Probably a Tea Party plot.g

[Sleek Geek]

Originally Posted by CaptainDan99

Check all of the connections to the fluxgate compass. Make sure they are tight and clean.

Is this a ST4000 or a ST4000 Plus? What happens if you push the -10 button in auto. Does the wheel turn to port?

-10 does not work either. I will go back and check all the connections to make sure they are good and clean. thanks for your help

[CaptainDan99]

Look on the front and see if it says ST4000+.

Try the +10 button in both stby and auto. Do the same for the -10 button and let me know if the wheel moves for each.

[MikeinLA]

Originally Posted by jrd22

Probably a Tea Party plot.g

Better right than left.

[srcody]

Listen carefully to the motor noises. Two days ago, beating in heavy seas, my AH800 quit steering, though I could hear the motor running and so on.

Opened it up later and the drive belting was OK, but a cog mounted on the motor shaft was able to turn freely. This is hard to spot, as the motor shaft is shiny and hard to turn by hand.

I guess they had superglued it at the factory, there was a kind of crust on the shaft after I slid it apart. Maybe the shaft overheated, maybe the torque was just too much.

I will reglue it after scraping off the residue. Thought about installing a setscrew, but I will try this first. Perhaps today's superglue is better. Acetone scrub first, as well.

28 ft Southern Cross cutter "SIRIUS" Penobscot Bay

[srcody]

Oh, yeah----typically the motorized ram drive, powered by a small motor is driven in or out by a 4-transistor "bridge". This allows the polarity applied to the motor (2 wires) to be REVERSED, so that the motor runs in the opposite direction.

If all the other functions seem normal, I might suspect the pair of transistors that controls that direction to be at fault. These would be spotted as in a group of 4, and relatively big. In my AH800, these are "TO220" standard packages. (plastic, with metal tab on top, 3 terminals on other end) Not a big deal to replace....