Honda BF35A-BF45A Outboard Motors Shop Manual., Page 232Get this manual
Because the piston lowers and pressures the oil in the oil chamber when the outboard motor is struck with an obstacle while cruising, the shock valve opens and oil enters between the piston and free piston to absorb the collision impactWhen the outboard motor is away from the obstacle, the piston rises by the dead weight of the outboard motor and the thrustThe oil between the piston and the free piston flows through the return valve in the piston to the oil chamber I 7m2