MANUAL HYDRAULIC PUMP - engages the backup hydraulic pump to the main engine.
Pressure generated by the pump is measured by a gage on the backup hydraulic panel.
Pressure should be 125 to 150 psi to engage the pump with the main engine.
BACKUP HYDRAULIC CIRCUIT DUMP VALVE - when opened, permits the backup pump
to disengage from the main engine. For the backup pump (and backup pump hydraulic
circuit) to function, this valve must be closed.
SELECTOR VALVE - determines which pump hydraulic circuit is to be activated. When the
valve handle is pushed in, the primary pump hydraulic circuit is selected. When the handle
is pulled out, the backup pump hydraulic circuit is selected. For the hydraulic system to
function, the appropriate pump must also operate.