Principles Of Operation - Suzuki DF 25 Service Manual

PRINCIPLES OF OPERATION

TRIM/TILT "UP" CIRCUIT
The electric motor is operating in a clockwise direction. Check valve A will open, allowing oil to flow from the
reservoir to the pump. Oil flow from the pump enters the spool valve, moving it to the left, opening the "down"
pressure main check valve and returning oil from the upper cylinder chamber (plus oil from the reservoir) to
the pump. Pressure built up by the pump will then open the "up" pressure main check valve and oil will enter
the lower cylinder chamber.
When trim motor stops, both the "DOWN" pressure main check valve and the "up" pressure main check valve
will close to retain tilt/trim position.
When full trim/tilt "up" position is attained, sustained operation of the "up" relay will have no effect, as pump oil
flow will be returned to the reservoir through the "up" relief valve.
Oil reservoir
PTT motor
Check valve
Gear pump
Spool valve
"DOWN" pressure
main check valve
POWER TRIM AND TILT
Tilt rod
Piston
"UP" pressure main check valve
"UP" relief valve
9-15
Upper cylinder chamber
Lower
cylinder
chamber