Robertson AP has stopped working

[Bob Bradley]

This unit was working since I owned the boat, but late last year it stopped. All the lights come on, and the heading window shows the correct course, but it does not control the boat, either automatically, or by manually turning the steer knob on the unit. Does anyone have any suggestions on where to start trouble shooting?
Bob

[Genesis]

Is the course number steady?

My fluxgate compass is hosed, and you can't get them anymore. I think I'm going to have to replace the entire unit - you can't get parts for these anymore.

I love that silly thing, but its been acting up intermittently for a year or so..... I guess its just plain time.

I DID fix it once when it was getting nasty - took the head unit down, opened it up, and reflowed all the solder connections on the board. That fixed it for a couple of years.

[Bob Bradley]

I thought it was steady, but I can't really say for sure. I'll check it out over the weekend and update then. It had been working perfectly, and then just quit. No intermittant problem leading up to that.

[Genesis]

When in "power steering" mode do the dodge buttons work?

If not, and the mode doesn't switch, then the rotary switch is at fault.

If so, then check the course heading UNDER WAY closely. At the dock it will be steady even if the compass is hosed. Its when moving that the course starts bouncing around wildly - if that's going on the unit goes insane trying to figure out where the boat is actually pointed.

[Bob Bradley]

No. Neither Dodge Buttons nor Rotary course adjustment control seem to have any effect. I believe I tried them both on "Auto" and on "Power Steer", but I'll verify this again as well.

[Tom Ipock]

Check to make sure the tiller rod has not become detached at the rudder. This happened to me once. I just replaced an AP100 that was hit by lightning. Kept all the components. May be something there you can use?
Tom

[Genesis]

If it comes on then the rotary switch may be at fault. Tear it apart and have a look. The computer is in the head and if the seal gets compromised or the unit gets wet inside you can have all kinds of "interesting" problems.

[Bob Bradley]

Tom, It's quite possible that I may need some parts. Let's stay in touch. You can email me by constructing an address out of: rbradley04 at snet.net

I looked at the backside of the unit when I was installing a new VHF last year, and there sure isn't much there. Mostly wiring contact points. I'll check the rudder connection as well.

[SKYCHENEY]

Does the pump run?

[Genesis]

If you remove the head unit you will find a number of screws around the perimeter of the case on the back. Remove them and the back cover comes off, exposing the circuit board.

[bigbill]

genesis, i have a 1993 model robertson ap300dl, my fluxgate compass went south, sea trac marine in new orleans sold me a new model [rate compass r c 25]it should be compatable if you have the same unit. after installing it the compass didn't solve my problem, i still have a [controll unit failure]. simrad, who ownes robertson said they no longer make that unit and i must buy a new unit. i am in the process of looking for a used controll head, much cheaper than a whole new unit.seatrac tells me i only have to purchase a control head and a junction box, the new compass will work with everything else in my system. the rate compass is about 550.00 dollars. bigbill

[Genesis]

For $550 I may just buy a new unit.

I have an AP200DL; its a very nice unit, but its WAY past its prime. I do have it interfaced and it will do the "NAV" mode, not just "auto", but still...

I'm considering ripping it out and putting in a Navman or Furuno..... The Navman comes with a rate gyro standard!

Check THIS sucker out...

http://www.navman.com/marine/products/autopilots/pilot3380/index.html

[DLCameron2]

Hello:

I need the bridge control head for my Robertson AP. I would be interested if any of you guys end up replacing your units; please let me know if one is available. Thanks.

DC :)

[Genesis]

If I rip mine out and replace it I'll post the announcement here, along with what parts I have that are believed good.

[Ezbry]

If you have checked what other have suggested you might then
check and see if you are getting voltage to your pump. Using a volt meter at the terminals at or near the pump have someone activate the auto pilot controls manually and check to see if you then get voltage. If you have voltage then you might need new brushes in the pump motor, if no voltage then go to the junction box and see if you have voltage coming out to the junction box while someone is manual using the autopilot controls. If not then you might need a new power board at the junction box. I have had similar problems on my ap300.

[SIDNEYF]

From New Registered Member-sidneyf......
Coincidently As I Was About To Post A Complete Robertson Autopilot Model Ap- 200DL For Sale I Came Across The Problem With A Members Unit. Sorry I Have No Advice To Offer,and Just As Well As There Seems To Be A Plethora Of Experts Available With A Great Deal More Knowledge Than I Could Ever Hope For. My Congradulations To All Of And I Hope Someday To Be Able To Contribute Some Help To Other Members. Anyway, I Have Just Replaced My Entire Autopilot System With A New Ap-20 Unit And Have The Following For Sale:

2- control heads
1- RFC 200 compass
1- J Box
1-RF-100 Rudder Feedback
1-DS-200 Distribution Panel
1- Hydraulic Pump


i would prefer to sell as a complete package, however, maybe different folks can use different components. Also, I have a complete set of cables, connectors and wiring looms.

Anyone interested can contact me at:516/817-4406 or SFOPSALES@AOL.COM

[SIDNEYF]

I Think I Also Have Finally And Maybe To Suggest.
Do You Have Sufficient Hydraulic Oil In The Container?
Is It Properly Pressurized?
Academic,to Be Sure, But Sometimes The Most Obvious Is Frequently Overlooked. Been There/dne That.
Sidneyf

[Bob Bradley]

Interesting suggestion on the hydraulic fluid. I have had an occasional odd leak, where hyd fluid appears from the base of the steering wheel. Not sure how it could get there from the AP pump, but I'll investigate that as well. Thanks again everybody for your suggestions.
Bob

[Tom Ipock]

Interesting suggestion on the hydraulic fluid. I have had an occasional odd leak, where hyd fluid appears from the base of the steering wheel. Not sure how it could get there from the AP pump, but I'll investigate that as well. Thanks again everybody for your suggestions.
Bob


I had that same problem occure and found it to be the air presure in the tank had leaked down just enough that the seal at the steering wheel would drip slightly. Pumped it up with bicycle pump and no more problem.
Tom

[SKYCHENEY]

FWIW, when I bought my boat, the previous owner said that the AP100 didn't work. I filled the oil and pumped up the pressure to where it should be and it has worked fine ever since.

[Bob Bradley]

Hmmm. First time out this season, I pulled out of the slip and only then realized that I had absolutely no steering. I spun her around using the engines, and managed to back into the slip unscathed, and went down and pumped up the cylinder. Steering is fine now, and I haven't seen any leaks this season.

[jim rosenthal]

Just curious...why should the hydraulic steering, which is Hynautic, NOT work if the reservoir is not pressurized? I thought pressurizing the reservoir was just to avoid foaming and keep air bubbles from forming. I don't think that any of the steering effort comes from the small amount of pressure that is held in the reservoir. The Hynautic helm units have stepped pumps that each push fluid along as you turn the wheel and the cam operates the pumps. Maybe you have a fluid leak or something is wrong with the helm.
Now, maybe the air pressure keeps priming volume in the helm unit and little pumps...maybe that's what it's for. If someone would post on this, I'd apppreciate it- would like to know more about it, since I have one of these systems.

[Bob Bradley]

I can't say why, Jim. The broker who sold me the boat is a regular on another local Hatt 45, and he warned me about the possibility of losing steering if the pressure dropped much below 10 psi. When I had no steering, that's the first place I looked and the pressure was down to almost 0. I pumped it up to 15-20psi, and lo and behold, it worked fine. That said, the AP still out to lunch. And NO, I didn't have a chance to try any of the above suggestions, as I didn't get out last weekend.

[bigbill]

jim, most of these systems have the reservior tank lower than the helm, the air pressure forces the fluid up to the helm [pump]. if the fluid ever gets low enough the air will go through the system, then the unit would have to be blead free of air. bigbill