Wonky Autopilot

[Gary Wyngarden]

We just came back from a three-day shakedown cruise in preparation for our two-month outing on the West Coast of Vancouver Island. Last Tuesday the ST 4000 Autohelm functioned perfectly. The next time out on Sunday, it was wonky.When it's on standby, a loud hum emits from the motor. When you push auto, it promptly begins a turn to port in increments of about 5 degrees with about a five second delay between turns, and it keeps going.Voltage readings taken at the power supply to the motor are very erratic.Between Tuesday and Sunday I finished my radar installation, pulling through the cable from the radome to the display and also testing the radar.My working hypothesis is that I snagged a ground wire loose on the autopilot when pulling through the cable and that's what I plan to check first. But I'm also thinking the radar might have done something to the fluxgate compass.I REALLY want to have this fixed before taking off for two months. Any advice will be appreciated.Gary WyngardenS/V Wanderlust H37.5

 

[J.B. Dyer]

Customer Support

Gary:I had some problems with my 4000+ earlier this year. I submitted the symptoms to the Ray Marine Customer Support via e-mail through their web site, which is reviewed by their tech's, and I got a response the very same day. It turned out that master unit was fried. I had to send it in and they didn't fix it, they just sent me a new one for 150.00, out of warranty of course. I've attached their web, but just in case it doesn't take, it's raymarine@custhelp.comLuck with it.

 

[Phil Herring]

Fluxgate compass

Has the unit worked in the past? Has anything changed around it? The fluxgate is subject to input from other electronics and who knows what -- it's location could be the issue.

 

[Rick D]

Humming 4000

The hum is interesting. Yes, I'd check all the connections first. If it worked OK before, I doubt the radar has caused the failure electronically. I once had the head unit fail but never had the noise you describe nor the voltage swings. Check that first, then do a new calibration of the head. If that doesn't work, it's off to Raymarine. Good luck, Rick D.

 

[Phil Herring]

Time to take my Evelyn Woods class again

I speed read right over the voltage swings... check that fluxgate theory. Between that and the hum it's gotta be in the wiring. Check with Ray Marine. I'll bet they'll recognize the 5 degrees increments and from my experience their CS folks are _fast_ and very good.

 

[Trevor - SailboatOwners.c]

Gary, try local RayMarine dealer

Hi Gary -Try calling Eddie at The Offshore Store in Seattle... he can be reached at 206-632-3025. I'm envious of your upcoming trip! I won't make it out to the west coast of Vancouver Island this year - have a GREAT TIME!Trevor

 

[Allen]

One thing about the voltage...

Gary,You said that the voltage to the motor is erratic. It should be. If the motor is not being asked to turn the wheel, the voltage should be 0. If it is being asked to turn the wheel, it will be higher. I don't think that's the problem.I'd check the supply voltage to the head unit. The head unit's supply voltage feeds the entire autopilot & sea talk system. If THAT's erratic, there's your problem. On my St4000 I think there's a warning if the voltage gets too low, though. If your unit isn't showing any warnings then it may not be that.As for the compass, I'd perform the "swing the compass" calibration before moving it. If the new radar installation is the problem then it will show up as a high deviation value. If the deviation value is still low, then you know the compass is fine.You definitely have something wierd going on there, though. Can I ask a few questions??1. Does the autopilot work better/worse/the same with the radar on?2. Is the autopilot wired to the radar via sea talk?3. If so, you may want to have your radar disconnected from the sea talk network to see if there's some sort of incompatibility going on there.4. Does the radar & autopilot share a common power source or circuit? If so, you may want to give the radar a dedicated power source and see if that helps.I have an ST4000+ MkII connected via sea talk to an RL70RC radar/chartplotter with no problems. I don't have a radar antenna (I just use the chartplotter functions) but it's a great set up with no compatibility issues at all. It's probably something as simple as a loose or corroded wiring connection.Good luck! Let me know if you need any help and feel free to email me directly at allenschweitzer@yahoo.com if you need more info on how I installed mine.Allen Schweitzers/v FalstaffC-30 Hull# 632

 

[Gary Wyngarden]

More Information

Well yesterday afternoon's project was to get further into this. I pulled the control head and found all wires securely attached. The incoming voltage from the breaker panel was at 12.6 volts (yes it's on a separate circuit and there's no seatalk bus). Voltage at the drive terminals on the back of the control head is at 1.7 when the unit is on standby and ranges from 0.5 to 10.5 in the auto position. The ohms readings for the wires leading to the drive unit are zero so those wires are intact. The voltage readings at the drive unit mirror those on the drive terminals of the control head.My new working hypothesis is that the control head is somehow fried. I have an email into Raymarine. Thanks for your help and suggestions so far. Any new ideas will be appreciated.Gary WyngardenS/V Wanderlust H37.5

 

[Rick D]

Hey, Gary

Years ago, someone on this board reported the motor was the same as one available at hobby stores and that he'd paid way less than factory. Just an FYI; doubt if you have the time. Rick D.