Raymarine autopilot issues

[cardude01]

My boat has an older Raymarine “smart pilot” autopilot with a ST60 control unit. I’m on a trip running about 8 hours per day using the AP. It works fine for the first 6 hours or so, and then the AP lose the compass heading and the AP wanders way off course. I’ve tried to swing the compass multiple times to get it synced back up, but I can’t get to the 5 degree standard.

Could my fluxgate compass be going bad? Or another part of the system maybe? Wonder why it works fine for so long then always goes haywire at the end of the day. Heating up from use?

This is what the plotter looks like after it loses its heading, or whatever is happening. Sometimes it just spins around and around!

https://youtu.be/cldirtJbT4c

Any help appreciated!

 

[boomerang]

Do a 360 in standby and watch the compass heading. It should fluidly count up the heading degrees. If you see it skipping a large segment of the compass quadrant, the compass is probably bad.
Those pilots are know for compass circuit failure. We have the same ST6002 /S1 corepack pilot on our boat and had the same issue. It's performing perfectly now after I replaced the Raymarine compass with one using NMEA data.

 

[cardude01]

So the fluxgate compass itself is going bad you think? I have a spare computer for the smart pilot, but not not a spare fluxgate.

 

[boomerang]

spin the circle and you should see if the compass is bad. The compass is a cheap part. The computer is the hard part to find so you're in luck.

 

[cardude01]

Thanks so much for the info. Now to try to find one.

When I spin I a circle the compass goes totally haywire.