Autopilot Hunts

[CHSBoater]

After working great for 3 years, my autopilot developed a world of problems.

Based on advice received in the old forum, I sent the SPX30 controller and fluxgate compass back to the factory for repair. After reinstalling, I discovered my Seastar Smart Stick was also faulty, so I replaced it. Now, after a factory head reset and performing and passing the dockside wizard tests, compass deviation test (3 degrees) and sea trail wizard tests, the autopilot hunts when used in the AUTO mode.

At low speed, it keeps a reasonably straight course but you and see the motors being turned to port and starboard constantly. At speed, it steers the boat in an S pattern, 5 - 8 degrees to starboard, 5 - 8 degrees to port, 5 - 8 degrees to starboard, and so on.

I lowered the response level to 2 without effect. I am sure there is some other setting that needs to be adjusted, but I am unaware of exactly what counter rudder, rudder damping, and such do.

Setup is e7 (data master), E120W, SPX30, ST70 Control Head, Seastar Smart Stick Rudder Reference, Seastar Hydraulic Pump. Software v 6.27

Pursuit 315 Offshore w 300 Yamahas.

Thanks for any and all suggestions
Tom Uffelman
Charleston, SC