Assembling The Gear Pump Assembly - Yamaha F150B Service Manual

2. Check the down-relief valve b. Clean if
there is dirt or residue.
3. Check the main valves c and shuttle
pistons d. Clean if there is dirt or
residue.
4. Check the absorber valve pin e and up-
relief valve seat f. Clean if there is dirt
or residue.
5. Check the valve pin g and valve seat h.
Clean if there is dirt or residue.
e
f
b
g
h

Assembling the gear pump assembly

• Do not use a rag when assembling the
PTT unit because dust and particles on
the PTT unit components can lead to
poor performance.
• Do not reuse the O-rings, always replace
them with new ones.
1. Install a new O-ring a, the up-relief valve
seat b, ball c, absorber valve pin d,
and spring e.
e
d
b
c
a
a
d
d
c c
e
d
c
b
a
2. Install new O-rings f onto the main
valves g, and then install the main
valves.
f f
g
3. Install the gears h.
h
4. Install the balls i, shuttle pistons j, and
balls k.
i
i
j
j
k
k
k
i
j
TIP:
Apply grease to the balls and shuttle pistons
to prevent them from falling out of the gear
pump cover.
PTT gear pump
g
g
f
h
i
k
j
j
i
9-48
0
1
2
3
4
5
6
7
8
9
10
A