Hydraulic Considerations – Legacy 2.1 L Pump
Different boats have different hydraulic considerations you must examine before mounting the pump or disconnecting any hoses. Before starting the hydraulic installation, verify the type of hydraulic steering in your boat, and where to install the appropriate type of pump.
notice
If the hydraulic steering of your boat does not match the hydraulic layouts in this manual, contact Garmin Product Support.
Legacy 2.1 L Pump Hydraulic Layout on Single-Helm Boats
Shadow Drive
Starboard line
Return line
Port line
S R P 
Helm
Legacy 2.1 L pump (and motor)
Notes:
•Legacy 2.1 L pump (and motor):
◦Do not use the legacy 2.1 L pump on a system with an unbalanced cylinder.
◦Mount the pump horizontally if possible. Do not mount the pump vertically with the pump end (hydraulic connections) down.
•Shadow Drive:
◦Mount the Shadow Drive horizontally and as level as possible.
◦Install the Shadow Drive in either the port or the starboard hydraulic line.
◦Always install a length of hose between the helm and the Shadow Drive.
◦Install the Shadow Drive between the pump and the helm.
◦Do not install the Shadow Drive directly to the helm.
◦Do not install the Shadow Drive between the pump and the cylinder.
Port fitting | Starboard fitting |
Balanced cylinder
notice
Do not turn the system on until you bleed all the air from the helm, the Shadow Drive, the pump, and all the hydraulic lines. See page 34.
16 | GHP 10 Marine Autopilot System Installation Instructions |