Tilt Up Operation - SELVA MARINE Kingfish 25 Service Manual

Tilt up operation

When the up side of the PTT switch is pushed, fluid pressure created by the gear pump 2 causes
PTT fluid to flow into the up side of the shuttle piston c and pushes the up valve a, causing it to
open. At this point, the fluid pressure forces the shuttle piston c to slide to the down valve b. The
protrusion on the shuttle piston c opens the down valve b, which opens the return passage. Then,
the PTT fluid flows into the lower chamber of the cylinder to force the free piston 0 and the tilt ram
assembly A to move up.
The relief valve 3 of the fluid pressure passage will open when the fluid pressure is more than the
limit, while the relief valve 3 in the upstream will not operate in the trim range because the passage
is blocked with the free piston rubber seal g. The up-relief valve opens at 3.6 MPa (36.0 kgf/cm
522.0 psi) .
3
3
È É
h Fluid pressure passage
k Return passage
m Relief passage
2
a
b
c
È F25
É FT25
PTT unit
g
h
k
m
2
,
2
A
0
2-16