2-30
PTT unit
0
1
2
3
4
5
6
7
8
9
10
A
Trim ram retraction function
When the outboard motor is tilted up and held in place with the tilt stop lever and the PTT switch is
pressed to “DN,” the trim ram will be retracted.
Although the gear pump attempts to draw fluid from the tilt cylinder and trim cylinder lower cham-
bers, after the PTT switch has been pressed, fluid cannot be drawn from the tilt cylinder lower cham-
ber because the tilt ram is secured in place by the tilt stop lever. Only the PTT fluid from the trim
cylinder lower chamber can be drawn, and as the fluid pressure decreases, the trim ram retracts into
the trim cylinder. Since the tilt ram is secured in place, the PTT fluid pumped by the gear pump flows
into the tilt cylinder upper chamber to increase fluid pressure. As a result, the down-relief valve
opens, and the PTT fluid is released into the reservoir.
A
Return
B
Send
a
Tilt cylinder
b
Trim cylinder
c
Up-main valve
d
Up-shuttle piston
e
Down-shuttle piston
f
Down-main valve
g
Tilt ram
h
Down-relief valve
i
Trim ram
j
Reservoir
k
Gear pump
l
PTT motor
h
i
i
j
k
k
l
d
e
b
b
f
g
c
a
A
B
Summary of Contents for F150B
Page 1: ...SERVICE MANUAL 6BM 28197 5L 11 F150B FL150B ...
Page 4: ......
Page 211: ...6 34 Vapor separator 0 1 2 3 4 5 6 7 8 9 10 A MEMO ...
Page 311: ...8 32 Shimming regular rotation model 0 1 2 3 4 5 6 7 8 9 10 A Shim location F R P T3 T1 T2 ...
Page 351: ...8 72 Shimming counter rotation model 0 1 2 3 4 5 6 7 8 9 10 A Shim location F R P T3 T2 T4 T1 ...
Page 448: ...A 1 MEMO ...
Page 451: ......
Page 452: ...Printed in China Jul 2008 0 6 1 ABE E_4 YAMAHA MOTOR CO LTD ...
Page 458: ......