My
autopilot was originally a
Raymarine Type III hydraulic, which is actually a rebranded Hy Pro HS40.
It's a good pilot and it has always worked well.
Some years ago I replaced the
pump.
Then five years ago when I upgraded all of my
electronics, I replaced the
Raymarine computer with a
Simrad AC42, and I replaced the old
rudder position
sensor with a
Simrad RS300.
Since then I've had five years of good
service, with a rare intermittent problem with the
clutch (hydraulic bypass solenoid valve).
NOW what I've done is taken a perfectly good functioning
autopilot and made it inoperable
Getting ready for my big trip this summer, I bought a spare
pump, sent the old one out to be rebuilt, had the ram rebuilt with a new
seals kit from Hy Pro, and bought a new
clutch. I also bought the extremely expensive set of new hoses and banjo bolts.
I installed all of this and it doesn't
work. Somehow I got the hoses on wrong -- the older ram has different
ports and I stupidly connected it as if to one of the new ones, with the return port of the ram connected to the "B" port of the pump. Somehow the pump was able to move the
rudder to stb -- in extension -- like that. But not to port. Then I discovered my mistake.
On top of that, the pilot computer can't find the rudder
sensor. WTF? We didn't touch the rudder sensor. This analogue sensor (this is an RS300, not the N2K RS25) works not by resistance, but by giving different frequencies for different rudder positions. My multimeter shows that the pilot computer is receiving signals on its rudder sensor terminals. But at hard to starboard, the frequency suddenly drops to 0. I don't know whether that might be confusing the computer. It is possible that since I had my rudder out, the rudder stop position might have changed slightly and taken the sensor out of its range of movement. But there is no obvious way to change the position of the rudder sensor without drilling new holes and de-centering it, which doesn't seem right. Or moving the connecting rod down a bit in the arm, but it's supposed to be 1:1 with the crank end of the quadrant, so that doesn't seem right either.
What a mess! So I figure I have probably two separate problems, and I should start with the hydraulic problem. This is what I've come up with as a diagnostic procedure:
1. Verify once again that the hoses are connected correctly.
2. Verify good o-rings and connections
3. Repeat fill and bleed procedure.
4. Attempt dockside commissioning again using Virtual Rudder Feedback
5. If that fails again, then I will jump the clutch relay to hold the clutch open, disconnect
cables to the pump, and hot wire the pump leads. Verify system works in both directions.
6. If it fails, then this means I've blown out a valve or seal somewhere by having it connected wrong. In this case, I will substitute the old rebuilt pump to verify whether the problem is pump or ram.
7. If it's the ram, then I buy another seal kit and take it back for another
rebuild, or just buy a new ram.
Does that sound reasonable? Anyone have any tips?
Then with the rudder sensor:
1. Try dockside commissioning again after hydraulics are sorted.
2. Disconnect the sensor,
power the computer up, switch it off, reconnect -- in case it has some kind of find the sensor protocol.
3. Call
Navico tech support and ask about the meaning of the frequency readings I get. Ask them for a diagnostic procedure.
Reasonable? Anyone ever have any similar problems?