Yamaha F50D Building instructions

SERVICE MANUAL
F50D
FT50C
60A-28197-5L-11
YAMAHA MOTOR CO., LTD.
Printed in Japan
Aug. 2008 – 0.5 × 1 n
(E) Printed on recycled paper
F50D, FT50C

Preface
This manual has been prepared by Yamaha primarily for use by Yamaha dealers and their trained
mechanics when performing maintenance procedures and repairs to Yamaha equipment. It has
been written to suit the needs of persons who have the Bronze Technical Certificate of YTA (Yamaha
Technical Academy) marine or the equivalent basic understanding of the mechanical and electrical
concepts and procedures inherent in the work, for without such knowledge attempted repairs or ser-
vice to the equipment could render it unsafe or unfit for use.
Because Yamaha has a policy of continuously improving its products, models may differ in detail
from the descriptions and illustrations given in this publication. Use only the latest edition of this
manual. Authorized Yamaha dealers are notified periodically of modifications and significant
changes in specifications and procedures, and these are incorporated in successive editions of this
manual. Also, up-to-date parts information is available in YPEC-web. Additional information and up-
to-date information on Yamaha product and services are available on Service Portal.
Important information
Particularly important information is distinguished in this manual by the following notations:
The Safety Alert Symbol means ATTENTION! BECOME ALERT! YOUR SAFETY IS
INVOLVED!
A WARNING indicates a hazardous situation which, if not avoided, could result in death or
serious injury.
A NOTICE indicates special precautions that must be taken to avoid damages to the out-
board motor or other property.
TIP:
A TIP provides key information to make procedures easier or clearer.
F50D, FT50C
SERVICE MANUAL
©2008 by Yamaha Motor Co., Ltd.
1st Edition, August 2008
All rights reserved.
Any reprinting or unauthorized use
without the written permission of
Yamaha Motor Co., Ltd.
is expressly prohibited.
Printed in Japan

General information
GEN
INFO
0
Specification
SPEC
1
Technical features and description
TECH
FEA
2
Rigging information
RIG
GING
3
Troubleshooting
TRBL
SHTG
4
Electrical system
ELEC
5
Fuel system
FUEL
6
Power unit
POWR
7
Lower unit
LOWR
8
Bracket unit
BRKT
9
Maintenance
MNT
10
Index
A
Appendix
A
Contents

0
1
2
3
4
5
6
7
8
9
10
A
GEN
INFO
General information
Safety while working
............................................................. 0-1
Rotating part............................................................................... 0-1
Hot part....................................................................................... 0-1
Electric shock ............................................................................. 0-1
Propeller ..................................................................................... 0-1
Handling of gasoline................................................................... 0-1
Ventilation................................................................................... 0-1
Self-protection ............................................................................ 0-2
Working with crane..................................................................... 0-2
Handling of burner...................................................................... 0-2
Part, lubricant, and sealant......................................................... 0-2
Handling of sealant..................................................................... 0-2
Special service tool .................................................................... 0-3
Tightening torque ....................................................................... 0-3
Non-reusable part....................................................................... 0-3
Disassembly and assembly........................................................ 0-3
How to use this manual
............................................................ 0-4
Manual format ............................................................................ 0-4
Abbreviation ............................................................................... 0-5
Sealant and locking agent
........................................................ 0-6
Symbol ....................................................................................... 0-6
Special service tool
.................................................................... 0-7

General information
0-1
GEN
INFO
Safety while working
To prevent an accident or injury and to
ensure quality service, follow the safety pro-
cedures provided below.
Rotating part
9
Hands, feet, hair, jewelry, clothing, Personal
flotation device straps, and so on can
become entangled with internal rotating
parts of the engine, resulting in serious
injury or death.
9
Keep the top cowling in place whenever
possible. Do not remove or replace the
cowling with the engine running.
9
Only operate the engine with the cowling
removed according to the specific instruc-
tions in the manual. Keep hands, feet, hair,
jewelry, clothing, Personal flotation device
straps, and so on away from any exposed
moving parts.
Hot part
During and after operation, engine parts are
hot enough to cause burns. Avoid touching
any parts under the top cowling until the
engine has cooled.
Electric shock
Do not touch any electrical parts while start-
ing or operating the engine. They can cause
shock or electrocution.
Propeller
Do not hold the propeller with your hands
when loosening or tightening it.
Handling of gasoline
9
Gasoline is highly flammable. Keep gaso-
line and all flammable products away from
heat, sparks, and open flames.
9
Gasoline is poisonous and can cause injury
or death. Handle gasoline with care. Never
siphon gasoline by mouth. If you should
swallow some gasoline or inhale a lot of
gasoline vapor, or get some gasoline in
your eyes, see your doctor immediately. If
gasoline spills on your skin, wash with soap
and water. If gasoline spills on your cloth-
ing, change your clothes.
Ventilation
9
Gasoline vapor and exhaust gas are
heavier than air and extremely poisonous. If
inhaled in large quantities they may cause
loss of consciousness and death within a
short time.
9 When test running an engine indoors
(example: in a water tank) make sure to do
so where adequate ventilation can be main-
tained.

0-2
0
1
2
3
4
5
6
7
8
9
10
A
Self-protection
9
Protect your eyes by wearing safety
glasses or safety goggles during all opera-
tions involving drilling and grinding, or when
using an air compressor.
9
Protect your hands and feet by wearing
protective gloves and safety shoes when
necessary.
Working with crane
9
Outboard motors weighing 18.0kg (39.7lb)
and over must be carried by a crane.
9
Use a wire rope of adequate strength, and
lift up the outboard motor with the three
point suspension.
9
If the outboard motor does not have three
or more points to be suspended, support it
with additional ropes or the like so that the
outboard motor can be lifted and carried in
a stable manner.
Handling of burner
9
Incorrect handling of burner may result in
burns. Refer to the operation manual
issued by the manufacturer to assure the
correct handling.
9
When using a burner, keep it away from the
gasoline and oil, to prevent a fire.
9
Components become very hot enough to
cause burns. Do not touch directly.
Part, lubricant, and sealant
Use only genuine Yamaha parts, lubricants,
and sealants or those recommended by
Yamaha, when servicing or repairing the out-
board motor.
Handling of sealant
9
Wear protective gloves to protect your skin,
when using the sealants.
9 Refer to the material data sheet issued by
the manufacturer. Some of the sealants
may be harmful for human health.
Safety while working

General information
0-3
GEN
INFO
Special service tool
Use the recommended special service tools
to work safety, and to protect parts from dam-
age.
Tightening torque
Follow the tightening torque specifications
provided throughout the manual. When tight-
ening nuts, bolts, and screws, tighten the
large sizes first, and tighten fasteners starting
in the center and moving outward.
Non-reusable part
Always use new gaskets, seals, O-rings, cot-
ter pins, circlips, and so on, when installing or
assembling parts.
Disassembly and assembly
9
Use compressed air to remove dust and
dirt during disassembly.
9
Apply engine oil to the contact surfaces of
moving parts before assembly.
9
Install bearings with the manufacture identi-
fication mark in the direction indicated in
the installation procedure. In addition, make
sure to lubricate the bearings liberally.
9
Apply a thin coat of water-resistant grease
to the lip and periphery of an oil seal before
installation.
9
Check that moving parts operate normally
after assembly.

0-4
0
1
2
3
4
5
6
7
8
9
10
A
How to use this manual
Manual format
The format of this manual has been designed to make service procedures clear and easy to under-
stand. Use the information below as a guide for effective and quality service.
9
Parts are shown and detailed in an exploded diagram and are listed in the component list (see 1
in the figure below for an example page).
9
The component list consists of part names and quantities, as well as bolt and screw dimensions
(see 2 in the figure below).
9
Symbols are used to indicate important aspects of a procedure, such as the grade of lubricant and
lubrication point (see 3 in the figure below).
9
Tightening torque specifications are provided in the exploded diagrams (see 4 in the figure below
for an example), and in the related detailed instructions. Some torque specifications are listed in
stages as torque figures or angles in degrees.
9
Separate procedures and illustrations are used to explain the details of removal, checking, and
installation where necessary (see 5 in the figure below for an example page).
TIP:
For troubleshooting procedures, see Chapter 4, “Troubleshooting”.
Lower unit
8-17
LOWR
Removing the drive shaft and shift
rod assembly
1. Loosen the pinion nut 1 as shown.
2. Remove the pinion nut 1 , drive shaft 4 ,
oil seal housing assembly 5 , pinion 6 ,
and forward gear assembly 7 .
3. Remove the shift rod assembly 8 and
shift cam 9 .
Disassembling the drive shaft
assembly
1. Install the pinion nut 1 , tighten it finger
tight, and then remove the drive shaft
bearing 2 using a press. NOTICE: Do
not press the drive shaft threads a
directly. Do not reuse the bearing,
always replace it with a new one.
Disassembling the forward gear
1. Remove the taper roller bearing from the
forward gear using a press. NOTICE: Do
not reuse the bearing, always replace
it with a new one.
Drive shaft holder 4 2 : 90890-06518
Pinion nut holder 3 : 90890-06715
3
2
1
45
6
1
7
9
8
Bearing inner race attachment 3 :
90890-06641
Bearing separator 1 : 90890-06534
2
a
1
3
1 2
a
b2
Lower unit
8-1
LOWR
Lower unit (F50D)
2
3
8
9
9 N·m (0.9 kgf·m, 6.6 ft·lb)
9 N·m (0.9 kgf·m, 6.6 ft·lb)
35 N·m (3.5 kgf·m, 25.8 ft·lb)
40 N·m (4.0 kgf·m, 29.5 ft·lb)
8
4
4
56
4
1
411
18
10
19
12
13
14 15
16
17
76
No Part name Q’ty Remarks
1Lower unit 1
2 Plastic tie 1
3 Hose 1
4 Bolt 4 M10 × 40 mm
5 Check screw 1
6 Gasket 2
7Drain screw 1
8Dowel 2
9 Bolt 1 M8 × 35 mm
10 Anode 1
11 Bolt 1 M8 × 60 mm
12 Spacer 1
13 Propeller 1
14 Washer 1
15 Washer 1
16 Propeller nut 1
17 Cotter pin 1
41
2
3
5
Safety while working / How to use this manual

General information
0-5
GEN
INFO
Abbreviation
The following abbreviations are used in this service manual.
Abbreviation Description
ABYC American Boat and Yacht Council
API American Petroleum Institute
AT FAutomatic Transmission Fluid
AWG American Wire Gauge
BTDC Before Top Dead Center
CCA Cold Cranking Ampere
CDI Capacitor Discharge Ignition
C/L Centerline
D model Hydro tilt model
DN Downside or downward
EN European Norm (European standard)
EX Exhaust
FForward
H model Tiller handle model
IEC International Electrotechnical Commission
IN Intake
LED Light-Emitting Diode
N Neutral
PORT Port side
PTT Power Trim and Tilt
RReverse
R model Remote control model
RON Research Octane Number
SAE Society of Automotive Engineers
STBD Starboard side
TDC Top Dead Center
UNF Unified fine thread
UP Upside
WD Wiring diagram

0-6
0
1
2
3
4
5
6
7
8
9
10
A
Sealant and locking agent
Symbol
Symbols in an exploded diagram or illustration indicate the grade of lubricant and the lubrication
point.
Symbols in an exploded diagram or illustration indicate the grade of sealant and the seal point.
Symbol Name Application
Yamaha 4-stroke motor oil Lubricant
Gear oil Lubricant
Water resistant grease
(Yamaha grease A)
Lubricant
Molybdenum disulfide grease Lubricant
Corrosion resistant grease
(Yamaha grease D)
Lubricant
Low temperature resistant grease
(Yamaha grease C)
Lubricant
Symbol Name Application
Gasket Maker Sealant
LOCTITE 271 (red) Sealant
LOCTITE 242 (blue) Sealant
LOCTITE 572 (white) Sealant
Silicon sealant Sealant
ThreeBond 1377B Sealant
How to use this manual / Sealant and locking agent

General information
0-7
GEN
INFO
Special service tool
For all markets except for U.S.A. and Canada.
Special tools with Yamaha parts number (90890-*****) are distributed by Parts Division.
Drilling plate
90890-06783
Digital circuit tester
90890-03174
Peak voltage adapter B
90890-03172
Ignition tester
90890-06754
Test harness (2 pins)
90890-06867
Vacuum/pressure pump gauge set
90890-06756
Throttle sensor adjusting lead (3 pins)
90890-06857
Digital caliper
90890-06704
ThreeBond 1401 Sealant
Symbol Name Application

0-8
0
1
2
3
4
5
6
7
8
9
10
A
Test harness (3 pins)
90890-06870
Test harness (4 pins)
90890-06871
Digital tachometer
90890-06760
Compression gauge
90890-03160
Flywheel holder
90890-06522
Flywheel puller
90890-06521
Crankshaft holder 18
90890-06562
Valve spring compressor
90890-04019
Valve spring compressor attachment
90890-06320
Valve guide remover/installer
90890-06801
Sealant and locking agent / Special service tool

General information
0-9
GEN
INFO
Valve guide reamer
90890-06804
Valve lapper
90890-04101
Valve seat cutter holder
90890-06316
Valve seat cutter 30°
90890-06326
Valve seat cutter 30°
90890-06328
Valve seat cutter 45°
90890-06555
Valve seat cutter 60°
90890-06323
Valve seat cutter 60°
90890-06315
Bearing outer race attachment
90890-06626
Driver rod LS
90890-06606

0-10
0
1
2
3
4
5
6
7
8
9
10
A
Oil filter wrench
90890-01426
Piston slider
90890-06529
Shift rod push arm
90890-06052
Stopper guide plate
90890-06501
Bearing housing puller claw S
90890-06564
Center bolt
90890-06504
Bearing separator
90890-06534
Stopper guide stand
90890-06538
Bearing puller assembly
90890-06535
Driver rod L3
90890-06652
Special service tool

General information
0-11
GEN
INFO
Needle bearing attachment
90890-06614
Driver rod SS
90890-06604
Bearing depth plate
90890-06603
Bearing inner race attachment
90890-06653
Bearing inner race attachment
90890-06639
Needle bearing attachment
90890-06607
Drive shaft holder 4
90890-06518
Pinion nut holder
90890-06715
Bearing inner race attachment
90890-06641
Magnet base plate
90890-07003

0-12
0
1
2
3
4
5
6
7
8
9
10
A
Bearing inner race attachment
90890-06644
Bearing outer race attachment
90890-06622
Driver rod LL
90890-06605
Driver rod SL
90890-06602
Bearing outer race attachment
90890-06627
Leakage tester
90890-06840
Backlash indicator
90890-06706
Handle stopper
EU0-23814-30
Dial gauge set
90890-01252
Magnet base
90890-06844
Special service tool

General information
0-13
GEN
INFO
Pinion height gauge set
90890-06668
Ring nut wrench 3
90890-06511
Ring nut wrench extension
90890-06513
Bearing housing puller claw L
90890-06502
Needle bearing attachment
90890-06612
Ball bearing attachment
90890-06655
Bearing inner race attachment
90890-06661
Needle bearing attachment
90890-06611
Bearing inner race attachment
90890-06662
Bearing inner race attachment
90890-06643

0-14
0
1
2
3
4
5
6
7
8
9
10
A
Bearing outer race attachment
90890-06621
Pinion height gauge set
90890-06669
Bearing outer race attachment
90890-06628
Needle bearing attachment
90890-06615
Cylinder-end screw wrench
90890-06568
Timing light
90890-03141
Special service tool

General information
0-15
GEN
INFO
— MEMO —