Recently I upgraded to a Raymarine ST-4000 Mk2 autopilot on my H31. Everything seems to be operational expect the boat swings excessively trying to keep on course. It starts with small overcorrections and gets worse ending up with extreme swings. I think the answer relates to the "turn rate" function. The unit is designed for wheels that range from 3.5 to 1 revolution from starboard to port. H31 is about 1.25 revolutions. The manual doesn't have any information on this function. Has anyone installed or adjusted one of these units on a H31 or similar? Thanks, Mark.