Autopilot Troubleshooting

[Essobee33034]

Good morning! We have a Grand Banks 36 Classic that we are thoroughly enjoying. She's not perfect but it has been fun getting to know her. One of the bits that we have broken is the autopilot. It is a simrad robertson AP11 heads with what I believe to be the J3000 box. The drive itself is a mechanical drive mounted below the lower helm. When it was working there was a noticeable thump when you engaged the autopilot, as if a mechanical clutch was engaging. This is no longer occurring, and within a minute of asking the unit to steer, one gets an error message on the display "actuator fail".

The unit worked fine for our purposes prior to breaking, so fixing the current one is preferred to replacement. I have found the manuals for the head unit and the installation guide but cannot identify the type of mechanical drive this is. Anybody have any ideas on a troubleshooting guide for the mechanical drive seen in the pictures? It has no label or identifying numbers and may just be a custom metal box for a reversing electric motor.

 

[Portage_Bay]

It looks to me like there is a large solenoid on top to actuate the clutch lever.

I would start with the easy things first like checking the wiring and connections. And the output from the J3000 box to the solenoid as well as the reversing motor signals. Hopefully you have the Simrad manual to identify the connections.

Next get someone to engage the autopilot while you watch. If I'm right that these are solenoid and clutch lever but nothing moves then what you may have learned is there is a problem with the solenoid, it's failed or the wiring has failed. If the solenoid moves the clutch lever then the problem is internal. Bad connections inside the mystery box. Broken clutch. Who knows.

When faced with something like this with no information to go on I take the attitude "It's already broken" and start in. Carefully open and begin to disassemble, lots of pictures and notes as you go. It's probably repairable.

 

[Bmarler]

Agree, if it’s not clunking any more, the solenoid isn’t pulling in. Either the signal is lost, or the solenoid has failed.

 

[GMiller]

Thank you very much! I have removed the motor and without the service manual I will start with replacing the solenoid. Any idea what brand and spec this might be? Does this type of solenoid have a special name? Looks like a ink mark of h8 and 6836 on it, and a quick google search from my phone isn’t immediately revealing.

 

[Bmarler]

Thank you very much! I have removed the motor and without the service manual I will start with replacing the solenoid. Any idea what brand and spec this might be? Does this type of solenoid have a special name? Looks like a ink mark of h8 and 6836 on it, and a quick google search from my phone isn’t immediately revealing.

i would have started by checking voltage to the solenoid. or apply voltage to the solenoid and see if it pulls in.
you can get solenoids like the through Grainger or Mcmaster Carr. easy enough to cross reference by size and voltage.

 

[Essobee33034]

I am hanging wallpaper one-handed, with the control box under deck and the AP controls out of reach. SWMBO was not with me this afternoon, unfortunately. When I turn on the autopilot and engage it there is a slight click audible. I will investigate further when off on Wednesday. Thanks again for your time to respond.

 

[Essobee33034]

Circling back to this, I dismantled the motor box, brought the motor and solenoid home. Applying 12V to the solenoid moves it as it should. Applying 12V to the motor yields bupkus. Took it this AM to a generator/starter shop, should get it back next week. The proprietor was surprised, as someone took an old 6v Ford generator and used it in this application, he says likely because it spins more slowly.

 

[Portage_Bay]

Circling back to this, I dismantled the motor box, brought the motor and solenoid home. Applying 12V to the solenoid moves it as it should. Applying 12V to the motor yields bupkus. Took it this AM to a generator/starter shop, should get it back next week. The proprietor was surprised, as someone took an old 6v Ford generator and used it in this application, he says likely because it spins more slowly.

Congratulations on successfully diagnosing the problem and finding the solution!

 

[rgano]

Please tell us how it works out, and BTW, welcome aboard!

 

[adornato]

Please tell us how it works out, and BTW, welcome aboard!

Rich nice to hear from you.. trust Frolic did ok on the lift in Helene
bruce

 

[rgano]

Hey, Bruce. We got the "good" side with nothing more that water in the yard and 30 MPH gusts. Tied all four "corners" of the boat to pilings to prevent swaying about in the wind.

 

[Lepke]

Looks like they started with copying a Wood Freeman.

There's probably some parts on ebay.

 

[Essobee33034]

Post script on this. The motor had a new armature and internals placed for $250. He said he could get it to turn in both directions, but it only after helping it get started- it was on its last legs. I re-installed the motor and was very disappointed to have the same symptoms as when I started. So, taking the advice of the hive, I used a mm to trace the power from the J300x to the motor itself, as the install specs call for 10ga wire to the motor, and these wires look like 16ga, and maybe that was the problem. I was then surprised that the power leads led to a black box that I wasn't even aware of having been part of the AP system. I opened it up to find 3 mechanical devices (switches or relays?). Power entered the box through a breaker. On one side of the breaker there was 13v, only 6.5 on the other, regardless of switch position. I removed the breaker and did a brief test and it worked! Replaced the breaker and Bob's my uncle. Thanks all for the help.

 

[Bmarler]

The take away here is, always check the installation essentials first. Motors need power, so check that as a first course of action. It can save a lot of time and effort.
Congrats on getting it working again.

 

[rgano]

And thank you for filling us all in on your eventual fix. So many times we never heard the end of the story.