Looking for suggestions on fixing / replacing the autopilot on Mainship 430

My autopilot shorted out (it keeps triggering the breaker when I try to turn it on).





Any ideas on how to troubleshoot ?

it's 2000 vintage so I'm considering to replace it as well.

My new chartplotter is Simrad but I can switch to Garmin because they make it easier to work with navionics which is my choice of maps provider.

i'd prefer to stay in the same ecosystem so it should be Simrad or Garmin (if I switch) autopilot.

I understand i will need the pump, computer, control panel and probably the compass unit, right?

Anyone did such upgrade on the same or similar boat?

Which brand/model did you use?

Thanks for any useful info you can provide

With the pump disconnected it blows the circuit?
How about with the course computer power lead disconnected at the terminal?
That would qualify the power leads to the unit.
If the pump is disconnected, the power source qualified, and it blows the breaker when you hook up the course computer, the pump might still be ok to use with the next system.

Thinking a little more, I think I’d disconnect things from the computer one at a time and see if you can get the breaker to hold. It could be anything. Rudder feedback, compass, remote panel.

Thanks. I'll try that.

Do you know if I can use any computer with the old pump if it still works, or if I have to match the pump to the computer?

So if it pops immediately on startup it is possibly blowing the fuse before powering the pump I would start tracing wires looking for a short. Pumps are pretty much interchangeable. My personal choice is Octopus, available in several size steps and adjustable within each step to smooth out operation. Would try driving the pump with a fused jumper wire to verify operation if you suspect it may be the issue.

Ideally, i would keep the pump and replace everything else.
is it safe to power the pump with 12v to the lead wires to the pump to see if it works?

is this + to red and - to black to pump to one side and - to red and + to black to pump to other size?

yes, reversing polarity operates opposite direction

here is the set I came up with:

- Octopus Autopilot Pump Type 3 Adjustable Reversing 12v Up To 30ci Cylinder
- Simrad Nac-3 Autopilot Core Pack: Nac-3, Precision-9, Rf25n & N2k Starter Kit
and probably this one
- Simrad Ap44 Autopilot Controller

do you have any experience with Simrad NAC-3 and Octopus Type 3 pump?