Yamaha F50 Service Manual

62Y3A117-62
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No. Part name Q’ty RemarksTightening torques
Stage N·mkgf·mft·lb
1Bolt 2 M5 ×
 20 mm 5 0.5 3.6
2 Washer 2
3 Gear pump bracket 1
4 O-ring 2
Not reusable
5 Spacer 2
6Spring 2
7 Valve pin 2
8Ball 2
9 Manual release spring 1
10 Ball 2
11 Gear pump cover 1
12 Spring 2
13 Shuttle piston 1
14 O-ring 1
Not reusable
15 Valve seal 2
16 Circlip 2
17 Pin 2
18 Drive gear 1
19 Shaft 1
20 Driven gear 1
21 Ball 2
22 Shuttle piston 1
23 Valve plate 1
24 Plate 1
25 Gear pump housing 1
Gear pump 

BRKTBracket unit
7-6362Y3A11
Disassembling the tilt cylinder
1. Hold the power trim and tilt 1
 in a vise
using aluminum plates a
 on both sides.
2. Loosen the tilt cylinder end screw 2
, and
then remove it.
 WARNING
Make sure that the ram is fully extended
before removing the end screw.
3. Drain the fluid.
Disassembling the trim cylinder
1. Hold the trim cylinder 1
 in a vise using
aluminum plates a
 on both sides.
NOTE:
Place the trim cylinder in the vise horizon-
tally.
2. Loosen the trim cylinder end...

62Y3A117-64
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Disassembling the gear pump
1. Remove the manual release plug 1
 and
gear pump 2
.
2. Remove the relief valve bracket 3
, then
the down-relief valve 4
 and up-relief
valve 5
.
3. Remove the gear pump bracket 6
, then
the down-shuttle piston 7
 and up-shuttle
piston 8
.4. Remove the gear pump cover 9
, then
the down-main valve 0
 and up-main
valve A
. 
5. Remove the drive gear B
 and driven
gear C
.
Checking the tilt cylinder and trim 
cylinder
1. Check the power trim and...

BRKTBracket unit
7-6562Y3A11
3. Check the outer surface of the tilt piston
and free piston for scratches. Replace if
necessary.
4. Check the tilt ram for bends or excessive
corrosion. Polish with #400–600 grit
sandpaper if there is light rust or replace
if necessary.
Check the valves
1. Check the operation of the check valve
a
 of the trim cylinder end screw and
check the valve for dirt or residue. Clean
if necessary.
2. Check the operation of the tilt piston
absorber valve and check for dirt or resi-...

62Y3A117-66
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Checking the gear pump
1. Check the drive gear 1
, driven gear 2
,
and shaft 3
 for damage or excessive
wear. Replace if necessary.
Assembling the gear pump
1. Install the drive gear 1
, driven gear 2
,
shaft 3
, and pins 4
 into the gear pump
housing 5
.
2. Install the balls 6
 into the gear pump
housing 5
.
3. Install the down-main valve 7
 and up-
main valve 8
.
4. Install the gear pump cover 9
.
5. Install the shuttle pistons 0
 into the gear
pump cover 9
.
6. Install...

BRKTBracket unit
7-6762Y3A11
10. Install the filters J
 and gear pump K
 by
installing the bolts L
, then tightening
them to the specified torque. 
11. Install the manual release plug M
 and
reservoir cap N
.
12. Fill the reservoir with the recommended
fluid to the correct level as shown.
13. Install the joint O
 and power trim and tilt
motor P
 by installing the bolts Q
, then
tightening them to the specified torque.
Assembling the trim cylinder
1. Install the dust seal 1
 into the tilt cylinder
end...

62Y3A117-68
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4. Install the backup ring 5
 and O-rings 6
and 7
 into the trim cylinder end screw
8
.
5. Install the trim cylinder end screw onto
the tilt ram.
6. Install O-rings 9
 and 0
 onto the trim pis-
ton A
, and then install the trim piston to
the trim cylinder B
.
7. Install the backup ring C
 and O-ring D
into the tilt piston E
.
8. Install balls F
 and G
, absorber valve pin
H
, spring I
, pins J
 and K
, and washer
L
 into the tilt piston.9. Hold the tilt ram end in a vise...

BRKTBracket unit
7-6962Y3A11
13. Install the trim cylinder end screw N
, and
then tighten it to the specified torque.
CAUTION:
Do not damage the check valve b
 when
tightening the end screw.
Assembling the tilt cylinder
1. Install the valve seal 1
 and the circlip 2
into the free piston 3
 as shown.
2. Install the free piston into the trim cylin-
der 4
 by installing the circlip 5
.
3. Install the trim cylinder base 6
, springs
7
, and plate 8
 into the trim cylinder with
the circlip 9
.4. Hold the power...

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7. Install the tilt cylinder end screw C
, and
then tighten it to the specified torque.
8. Fully extend the tilt rod, and then add suf-
ficient fluid of the recommended type to
the correct level.
9. Install the reservoir cap D
.
Bleeding the power trim and tilt 
(not installed)
1. Close the manual release plug 1
 by
turning it clockwise.2. Place the power trim and tilt in an upright
position.
3. Check the fluid level in the reservoir.
NOTE:
The fluid level should be at the...

BRKTBracket unit
7-7162Y3A11
6. Connect the PTT motor leads 2
 to the
battery terminals.
7. Reverse the PTT motor leads between
the battery terminals when the tilt ram is
fully extended, and then reverse them
again when it is fully compressed.
NOTE:
Repeat this procedure so that the tilt ram
goes up and down four to five times.
The sound of the power trim and tilt motor
will change when the tilt ram is fully
extended.
8. Check the fluid level again when the tilt
ram is fully extended. Add sufficient...