[CA] [CA11] Upgrade pump on S1 course computer

[HappyHarry]

Hey guys,
Recently, I disassembled a complete autopilot set from another boat to be built into our boat.
These are: Raymarine (12 volts) ST8002, S1 computer, Compass, Gyro, Type 1 pump and Rudder sensor.
Since my steering cylinder is 650 cc, I think of a heavier pump like Type 3 but it can't be connected to the S1, according the manual.
Is there another solution to upgrade the pump with S1?
The only thing I can think of is a reversing relay between S1 and pump but is that possible, I don't know what the A and B ports gives, a steady voltage?
Thanks.

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum HappyHarry,

Please click here to view a FAQ addressing this subject. For a steering ram having a capacity of 650cc, a Constant Running Pump (12V or 24V) would be recommended. During the period in which the S1/S1G autopilot course computers were manufactured, a the Constant Running Pump (12V or 24V) would have been mated to a S3/S3G Autopilot Course Computer. With respect to hydraulic pumps, S1/S1G autopilot course computers should only be mated to a Type 1 hydraulic pump. Neither the S1 nor Type 1 pump would have been recommended for an application having the stated steering ram capacity.