"Crazy Ivan" the Autopilot

[reedbr]

I remember reading a submarine book once about the "Crazy Ivan" tactic, where a skipper would turn the boat abruptly 45 degrees to port or starboard without warning.  We have renamed our Raymarine 4000 autopilot to Crazy Ivan.  He only goes to port and usually only 20-30 degrees, but it is definitely without warning.  He usually comes back to course, or close to it, in about 2 minutes.  This weekend I played with some variables trying to identify the source of the problem but couldn't.  My clues are below.  They may be related or just misleading.  Toss out your theories though.  I have a week on the boat coming up starting Friday, so I'll have a chance to check them all out.   This is a '97 MkII. 

(1)  I used to think it was voltage fluctuation problem when the fridge kicked in as my batteries were weak.  However, I just replaced the batteries two weeks ago with no change.
(2)  I played with the circuit breakers trying to isolate possible interference.  I turned off the fridge for a couple hours and still had problems.
(3)  It happens with the engine running or not.
(4)  While I've never been happy with the heading control on the autopilot, I've sailed her for seven seasons and it wasn't always this bad.
(5)  The fluxgate sensor is mounted below the head sink, a whopping 12" from the engine block and alternator.  She was apparently delivered this way and I haven't found enough cable slack for a better position.
(6)  I recently hardwired my GPS in for power using cables from a previous GPS.  However, the new one is not connected to the NMEA/SeaTalk interface, just power.  I think the problem was this bad before the GPS hardwiring.  Interesting to note that I have an Autopilot breaker and a Nav/Com breaker (depth+knotmeter).  The GPS is on the autopilot breaker.
(7)  I was below yesterday adjusting my stuffing box with only the cabin light breaker on and only a Hella fan running.  While I was working, the fan pitch noticeably changed at one point, like the fan slowed down.  It could have been a voltage fluctuation or just dirt in the fan.  I thought it might be related.
(8 ) I don't have a good volt meter on board as my current one is a Harbor Freight special, good for telling 6 from 12 volts, but not 12.4 versus 12.6 volts.  I can probably stock a better meter for the trip.

OK, I'm sure you have ideas or questions.  Even diagnostic tricks would help.  Let me hear your thoughts.   I want Ivan exorcised before the end of the trip.  Thanks in advance.

[Bob K]

Brian,
I too have a Crazy Ivan.  In my case, he shows his head when the alternator kicks off (it overheats during high charging, and turns off).  When it turns off, the boat will abruptly turn 15 or 20 degrees.  It will turn the other way when it kicks back on.  I've always assumed the autopilot is reacting to a voltage spike or abrupt change in voltage, though I've never measured.  It doesn't happen often enough to make me want to fix it.  I just know to not venture too far from the helm when the autopilot is on, and the batteries are low!    I think your Harbor Greight DVM will likely be sufficient to measure a voltage change large enough to alter the pitch of a fan.  If it's a spike causing the issue, you'll need something more complex to see it, such as an oscilloscope.   Try playing more with the breakers to narrow it down.  Are any circuits bypassing the breakers (bilge pump?)  Good luck.....
Bob

[Ken Juul]

Most of the time we use a hand held VHF in the cockpit.  The first time we used the vhf at the Navsta (antenna at the mast head) we got the hard turn to port with every tranmission.  After some investigation we found the coax to the antenna was routed almost on top of the flux gate.  Rerouted the coax, problem ended.

The location under the sink has it close to alot of electrical interference.  The alternator as was mentioned, the ground cable to the electrical panel, etc.  Might want to get some lead foil or something to shield the flux gate it.

[reedbr]

So far, two camps, voltage fluctuation and magnetic interference. 

Interesting, I've always thought about moving the fluxgate, not shielding it.

If the problem is voltage fluctuation, my first choice would be to eliminate the cause.  Second choice would be to limit the effect.  Could I stick a capacitor or resistor on the autopilot circuit to smooth the voltage?  I used to do this with car stereo's.

Typically bad connections and bad grounds are the first place to look for mysterious voltage noise.  The battery connections, being new, were recently cleaned.  What other connections are suspect?

[Bob K]

Ken may be on to something....my alternator controller is located about 24" above my fluxgate compass (both in the hanging lacker).   A voltage spike can interfere with electronics much like a VHF radio can, as both emit electromagnetic energy.   I'm curious that you had only your cabin light breaker on, and experienced the shift in fan pitch.  I'd continue that experiment using your DVM.  The good news is that a week on the boat provides many opportunities to experiment and wait when hunting for intermittents.  Since it seems this change in autopilot heading is not an isolated event (the 3 of us and who knows who else have experienced it), I wonder if the Raymarine website FAQ or technical support may be of help. 

[Stu Jackson]

Brian,

I think you're on the right track.  Here are my initial notes on your first post:

Go to Radio Shack and break out the big boat bucks for a DVM.  Could be all of $20.  I've had mine for 35 years!

Keep asking the question:  "What cycles ON/OFF in (those) 2 minutes?"

What's the battery voltage.  Doesn't a Mark II come with a voltmeter in the panel?  Even my aftermarket analog voltmeter in my nav station works well enough for me to see varying voltages.

What's the voltage at the control head?  Disconnect it and turn it on and see the voltage(s).

What's the voltage at the batteries?  Whether they're new or not, only YOU know how you charge them and what condition they are in.

What charger do you have?  Is it connected when you're testing?  What stage is the charger in:  bulk, absorption or float?  Have you tried the test without the charger connected? (Obviously out on the water, but at the dock, too?)

What is the display on the control head saying?  Does it simply change headings all by itself?

Keep asking the question:  "What has changed recently?"  The autopilot should really be on its own breaker, based on all the directions in all the manuals I have ever read..  Try switching the GPS over to the Nav/Com breaker.  The depth sounder and knot meter are less susceptible to voltage fluctuations, as is the GPS.  Have you read the recent posts about belts on the 4000?  Are yours clean? (I put our new subwoofer - maybe takes an amp or two - on the sump - shower - switch.)

I don't have an answer, but these are the things I would do, playing detective, if it was my boat.

Finally, when it comes to electrical, "It's the Connections, Stupid!"  Really, almost always.  When was the last time you checked your engine ground?  Not by just looking, but by pulling on it, removing it and really checking it?

Good luck, keep us posted.

[Ron Hill]

Brian : When we went down the ICW, I met someone (at what seemed every stop) that was waiting for the return of their Autohelm 4000 from repair!!  Made me feel good that my Wheel Pilot worked flawlessly and still does 20 years later!

Anyway, I'd check the connections as recommend by Stu.  One of the most helpfull things I have on the boat is a can of "TurnerCleaner" from Radio Shake.  Just squirt some on a connection and it's lubed/cleaned.  A thought

[jmnpe]

Hi Brian,

Having the fluxgate compass mounted under the head sink is likely the root of your problem. I spent many hours crawling all over my boat with a hiking hand compass looking for a location that was actually a reasonable place for the fluxgate, and then rigging up a temporary mounting of the fluxgate to see if the AP would produce a reasonable "deviation" number after the "auto-calibrate" for the compass at a couple of "pre-screened" test locations.

When we bought this boat, the fluxgate had been located on the aft bulkhead under the port settee. The compass was about 10 inches above the macerator pump, which meant it was also about 6 inches below the large bundle of DC and AC wiring that routes around the same bulkhead. The AP was totally useless, going from doing nothing to taking off random directions. I can also confirm that below the galley sink is a constant magnetic storm...... I finally found a good location for it and it now works very well given its modest level of "smarts". Mine is a 4000+.

The best location I found was behind the interior liner directly behind the toilet, about half way between the head floor and the top of the counter behind the toilet ( a least on a Mk I ). I installed a 6 inch round access port, mounted the compass to the wide side of a piece of 2x4, and then screwed the 2x4 along the 2 inch side through the fiberglass liner with 2 #8 stainless steel screws. I had more than enough cable length once I went back and cut about 30 nylon cable ties off of the various places the compass cable was tied to anything that wouldn't move ( much... ) all the way back to the control head. You could probably do the same unless someone "tidied up" the wiring by cutting off the unused length of cable. Even if they did, the fluxgate compass wires can be lengthened with additional shielded 5 conductor cable to get where you need to go.

You have to appreciate that the magnetic forces being sensed by the fluxgate compass are very small, and getting smaller all the time ( literally... ). It doesn't take much DC current through a piece of wire in proximity to the fluxgate to change its perceived heading. While you can compensate out fairly large magnetic disturbances, that only applies to magnetic disturbances that remain fixed in location and strength relative to the fluxgate compass. A changing current through a wire nearby can't be compensated out.

My original practical education with fluxgate-compass-based autopilots on sailboats was in my first sailboat, a Hunter 25.5. I almost immediately installed a Navico TP5000 that we called "Nevil". Early on I noticed that sometimes when I would change sides in the cockpit, "Nevil" would go crazy for no apparent reason. After many observations through beer goggles, I finally realized I had car keys or a pocket knife in one of my pants pockets, and when that magnetic disturbance either arrived or departed the area near the self-contained fluxgate compass in the TP5000 while on an established heading, the AP would react robustly and unpredictably to the magnetic disturbance change. After that I always cleaned out my pockets when I got to the boat, and all was well with "Nevil".

In my experience, the Autohelm/RayMarine 4000 series is not particularly sensitive to low voltage unless it gets really low where other instruments and radios on the boat are acting weirdly or not working at all. As Ron mentioned, it as very sensitive to RF energy over a fairly broad range of frequencies. It certainly wouldn't hurt to go over every connector and make sure all is well, since loose connections can do all sorts of things that defy description and prediction. As Stu and I constantly say, "Check the connections first!".

Hope this helps you get to the bottom of your problem, and potentially others that have experienced the "Crazy Ivan" maneuver.

Regards,

John
1988 C34 hull 728 SR WK
Otra Vez

[Bobg]

I have the same problem, this week the thing just went nuts again, the compass heading on the screen abruptly changes anywhere from 30 to 100 degrees  off from the mounted compass, I tried calibration to no avail, I quit using it, and while sailing today, I noticed the compass heading on the unit was the same as the mounted compass, so, with one eye to caution, I activated it and the thing worked.  I was pretty happy, went for a couple hours. and all of a sudden the boat did a fast turn to land, I shut it off and the compass screen was 140 degrees off from the compass heading.  I will check the connections.  Other than that, I don't know what to do, and will be following this post to see if I can correct what ever is wrong.  The thing worked well for the first 3 years I had the boat, only this summer it has been "crazy Ivan" and all I have done electrically is installed the solenoid upgrade and put a positive battery terminal post above the alternator door.  In all honesty, I am not sure where the flux gate compass is located on the boat.  I'll have to run it down.

[jmnpe]

For trouble shooting purposes, the following data will be very useful in tracking down your problems with the "Crazy Ivan" maneuver with your 4000 series Autohelm/RayMarine AP.

1. If the heading readout changes while the AP is engaged and the boat steers toward the new displayed heading, the problem is not the fluxgate compass. The AP displays only the selected heading that the AP is trying to maintain when the AP in engaged and does not change in response to movement of the boat.

2. If the heading display remains the same with the AP engaged, and the boat steers away from the displayed heading, then the problem is associated with the heading that the fluxgate compass thinks it sees.

As soon as you put the AP in Standby, the heading display changes from the selected heading to the heading it thinks it is pointing at that instant.

In Case 1 the problem is likely internal to the controller/computer unit. It could be a problem with the membrane +10 or -10 switches, or could be at the controller circuit board. In this case, the heading commanded for the AP to follow is spontaneously changing and the rest of the AP control loop is just following instructions.

In Case 2, the AP suddenly thinks it's on the wrong heading ( i.e. - not what the commanded heading is that is shown on the display with the AP engaged ) and the AP control loop is again just following instructions. In this case, it could be caused by magnetic interferences that I discussed in my previous posting, or it could potentially be a problem in the fluxgate external wiring, or even an internal problem in the fluxgate compass. If the new heading the AP tries to maintain is a anything close to 120 degrees, the problem is likely the loss of one of the 3 output leg signals from the fluxgate compass. In this case, the changes will probably be somewhat consistent in the heading change amount each time you get the "Crazy Ivan" event.

As another potential root problem for Case 1, the problem could be a software glitch in the microprocessor inside the controller/computer unit. It would be useful if those of you who have experienced this problem would get your user manual and read how to display the software version in you unit, and the specific model variant you have on your boat and post it here. From past experience with "new" products from RayMarine about 10 years ago, their initial software release on "new" products was often far from debugged: they let their customers do that for them..... If you complained within the warranty period, they would update your software for free. Once you were out of warranty, TS for you.... For some rather astounding price they would update the software, but ...

Again, the first things to check are the simplest: the connections. After that, if you are experiencing the Case 2 scenario, find out where your fluxgate compass is mounted and what is around it within about a 12 to 18 inch radius, then report back here.

The most important thing, however, it to determine which failure scenario your "Crazy Ivan" fits: Case 1 or Case 2.

I will try to respond promptly to any posting on this subject, particularly if you have fairly specific observations you can share. Maybe we can get Crazy Ivan back on his meds on your boat.

Regards,

John
1988 C34 sr wk hull 728
Otra Vez

[Bobg]

Thank you John very much, I definitely have the case one scenario, however when I shut off all power to the unit, and turn it back on, it powers up with the display still off by 30-120 degrees.  and then low and behold, I look down and it is matching my compass course again and will work, albeit for a while.  Thanks John,   Bob

[jmnpe]

Hi Bob,

That is definitely a weird problem.....

A few more data points, please:

1. What model/vintage is your AP?
2. When you just disengage the AP after an "Ivan" event ( i.e. - go to Standby from Auto ) what happens on the heading display? How does it compare to your ship's compass and the heading you were originally try to hold?
3. When you cycle power to the AP ( pull the CB ), does is the power-up heading shown the same as when you powered it down ( assuming a steady heading, of course, during the power cycle)?
4. On the times that the unit displays a heading in Standby that is significantly different from your ship's compass, and later shows agreement, have you maintained the same heading or changed headings significantly during the wait time?

Let me know and I'll see if I can come up with a better analysis than just "weird".

Thanks.

John

[Bobg]

John to answer your questions, not at the boat right now
1>  not sure what year, the boat is a 88, it is a 4000
2>  When I go to standby from auto, the heading still reads off by various degrees, 10 to 100 or so
3>  When I power the unit down and then up, the heading stays the same, that is, still off by many degrees
4>  The course is maintained within a few degree,

John I am not at the boat right now and trying to answer from memory, the unit is hard to diagnose because it my go for a few days flawlessly, then just take off.  This week from Sunday to Wednesday, Sunday it worked, shut if off at anchor for a couple hours, and it wouldn't work again when I started it up Sunday night, it worked a half day on Tuesday, and half day on Wednesday, I shut the unit off wed about 11 am, turned it on about 12 am and crazy Ivan started up again, that's where it sits now, am going to the boat today, Thanks  Bob

[reedbr]

OK, I just got back from a week plus cruise on the Chesapeake with "Crazy Ivan".  True to form for intermittent problems, this one didn't resurface when I was ready for it.  It didn't reappear until the last day on the boat.  I was able to do some diagnosis, but it was limited as I had nine people on the boat for the last four days (yes, cruising with 9 onboard, 4 adults and 5 kids ages 10-15).  Here is my secondary set of notes:

- It is an Autohelm ST4000 vintage 1997, not a plus.
- I found some spare cable bundled up under the head sink, so I moved the fluxgate sensor 3 feet further to port and away from the engine.  The new location was right behind the head trash can.  This was done before the problem resurfaced.
- "Crazy Ivan" happened twice within 30 minutes of each other, both times while motoring north.  This was after the fluxgate sensor was moved.
- The change was still the same, 20-30 degrees to port, returning pretty close to the original course within 2 minutes.
- After the first incident, I unplugged the GPS and ran it on it's own internal battery.  It happened again while the GPS was unplugged (GPS is on the autopilot circuit).
- After the second time, I turned off the refrigerator but also had to change course to go upriver.  I went 30 more minutes without issue but then I was home.
- Most of the previous trip when the problem was bad I was heading north.  I was mostly motoring on that trip but it also happened under sail, also heading north. 
- Most of this recent trip I was heading south and Crazy Ivan was mostly on holiday.
-  Batteries were in good condition when the problem arose, having been plugged in at dock the night before.
- All during the week I could still hear the cabin fans changing pitch occasionally.  The integrated voltmeter on the panel didn't show any discernable jumps.  With that number of people on board, I was unable to pull the cushions and clip a digital meter on the battery posts for better readings.  Turning most equipment off for diagnostics also wasn't an option at the time.

So I still haven't fired Crazy Ivan.  However, if we go back to our original question on whether the problem is voltage fluctuation or magnetic interference, I'm leaning towards magnetic interference.   Of course, my experience is that the hardest problems usually have two causes which screws up diagnosis.  If I have any more to add after my Labor Day cruise, I'll post it here. 

Thanks for all your suggestions.

[jmnpe]

Hi Brian,

Thanks for the more detailed information. One thing you didn't note was what was happening to the heading readout during the "Crazy Ivan": did it remain steady at your selected heading, or did it shift to the new heading the boat would try to hold and then back to the original heading?

Since your boat is a Mk II, I am not as familiar with what all is in the areas under the head sink. The thing you will want to be aware of back there is any DC power cables that happen to run through the area, particularly ones that carry any significant amount of current. If you were hearing fans speeds changing while underway, you were definitely having non-trivial DC loads cycling on and off. The "usual suspects" are refrigeration, bilge pumps, and fresh water pressure pumps. Since both episodes occurred while motoring ( i.e. - alternator producing output), I would be particularly observant of how and where the alternator feed runs to the Nav station and the DC distribution panel.

Hopefully, your Labor Day outing will be a little less "populated" and you can do a bit more variable elimination. Don't forget, too, that people and the stuff they carry with them in pockets or purses and also create transient magnetic disturbances, so you have to also be aware of where your guests or crew are relative to the fluxgate sensor during a "Crazy Ivan" event.

Regards,

John