TOHATSU MFS 2 User manual

OB No.003-21058-0
07-04 NB-2600
Printed in Japan
OB No.003-21058-0
07-04 NB-2600
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Introduction
Before reading this manual
This service manual provides information that is needed for inspection, service and repair of applicable
outboard motors. For information about operation of the products that are not described in this
document, refer to the owners manual. For our customers' safe and comfortable use of the products
for long term, it is essential to maintain the performance and quality of the outboard. To ensure this,
the maintenance and service have to be done properly by service technicians with fundamental
knowledge and skills. This manual is utilized so that our customers can always use their outboard
motor with full satisfaction.
Information for securing of safety
Safety Statements
The following safety statements are found throughout this manual and indicate information
which, if ignored, could result in fatal safety hazards or property damages:
Provides an important one-point advice.
WARNING
Indicates the presence of a hazard or an
unsafe activity which, if ignored, could
result in severe injury or death.
DANGER
Indicates the presence of a hazard which, if
ignored, will result in severe injury or
death.
CAUTION
Indicates the presence of a hazard or an
unsafe activity which, if ignored, could
result in minor personal injury or damage to
the products or facilities.
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ii 4st 2/2.5/3.5 2007
Description of Pictogram
OIL RPM
O K
4st
OIL
2st
OIL
ATFATF
OIL
TEF
GREASE
LIT
GREASE
G17G17
BOND
OIL
GEARGEAR
GREASE
OBM
OBM
TB
13421342
TB
1373B1373B1373B
TB
11071107
OIL-COMP.
GM
SOCSOC
INS
GREASE
271271
LT
271518
LT
r/min
6 N·m ( 4 lb·ft ) [ 0.6 kgf·m ]
Example :
Maintenance
Service
Information Service Data
Specified
Electrical
Value
4 stroke
Engine Oil ATF DEXRON
III Gear Oil
2 stroke
Engine Oil
Screw Lock
Agent
[Three Bond®]
• 1342
Lubrication
Oil
Fuel System
(Carburetor)
Special Tool
Specified
Measurement
Value
Lower Unit Electrical
System
Power Unit
Troubleshooting
Tightening
Torque
Accessories Wiring
Diagrams
Bracket
The following symbols represent the contents of individual chapters.
The following symbols indicate items needed for the service.
The following symbols indicate a point to which lubrication oil, sealing agent or screw-locking agent is to be applied.
Screw Lock
Agent
[Three Bond®]
• 1373B
Waterproof
Grease
Teflon® Grease
TEFLON
Oil Compound
[Shinetsu Silicon]
S.O.C
Low
Temperature
Resistant
Lithium
Grease
Insulating
Grease
INS
[Konishi Bond]
• G17
Screw Lock
Agent
[Loctite®]
• 271
Gasket Seal
Agent
[Loctite®]
• 518
Specified Part
Test Run
Adjustment
Engine RPM
Use Limit
SI unit US unit Former units (conventional)
Gasket Seal
Agent
• 1107
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iii
4st 2/2.5/3.5 2007
1.Service Information
1 Identification (Engine Serial Number) 1-2
2 Securing of work safety ………………… 1-2
1) Fire Prevention ……………………………… 1-2
2) Ventilation …………………………………… 1-2
3) Protection …………………………………… 1-2
4) Genuine Parts ……………………………… 1-2
5) Tools ………………………………………… 1-3
6) Recommendations on Service …………… 1-3
7) Cautions in Disassembling and
Assembling Components ………………… 1-4
3 Tools and Instruments…………………… 1-5
1) Test Propeller ……………………………… 1-5
2) Instruments ………………………………… 1-5
3) List of Special Tool ………………………… 1-6
4 Predelivery Inspection…………………… 1-7
1) Steering Handle …………………………… 1-7
2) Gear Shift …………………………………… 1-7
3) Engine Oil …………………………………… 1-7
4) Gear Oil ……………………………………… 1-7
5) Fuel Tank and Fuel Line …………………… 1-8
6) Rigging ……………………………………… 1-8
7) Inspection of Tilt Stopper ………………… 1-8
8) Inspection of Stop Switch ………………… 1-9
9) Cooling Water Check Port ………………… 1-9
10) Idle Operation ……………………………… 1-9
11) Propeller Selection ………………………… 1-10
12) Inspection of Forward and Reverse Shifts 1-10
5 Break-in Operation………………………… 1-11
6 Test Run ……………………………………… 1-11
7 Checks After Test Run…………………… 1-12
2.Service Data
1 Outline Dimensons………………………… 2-2
1）Engine Dimensions ………………………… 2-2
2）Clamp Dimensions ………………………… 2-3
2 Cooling Water System Diagram ……… 2-4
3 Wiring Diagram……………………………… 2-5
4 Specifications ……………………………… 2-6
5 Maintenance Data ………………………… 2-8
6 Tightening Torque Data ………………… 2-12
7 Sealant Application Locations ……… 2-14
3.Maintenance
1 Special Tool ………………………………… 3-2
2 Inspection Schedule ……………………… 3-3
3 Inspection Items …………………………… 3-4
1) Inspection of Top Cowl …………………… 3-4
2) Inspection of Fuel System ………………… 3-4
3) Inspection of Fuel Tank …………………… 3-4
4) Inspection of Fuel Cock (Fuel Filter)……… 3-5
5) Inspection of Fuel Cock …………………… 3-5
6) Replacement of Engine Oil………………… 3-6
7) Inspection of Gear Oil Quantity …………… 3-8
8) Inspection of Water Pump ………………… 3-8
9) Replacement of Gear Oil ………………… 3-10
10) Inspection of Gear Case (for leakage) …… 3-11
11) Inspection of Spark Plug…………………… 3-12
12) Inspection of Compression Pressure …… 3-13
13)
Inspection and Adjustment of Valve Clearances …3-14
14) Adjustment of Throttle Cable ……………… 3-16
15) Inspection of Gear Shift Operation ……… 3-17
16) Flushing with Water ………………………… 3-18
17) Inspection of Idle Engine Speed ………… 3-18
18) Inspection of Ignition Timing ……………… 3-19
19) Inspection of Anode………………………… 3-19
20) Replacement of Anode …………………… 3-19
21) Inspection of Propeller……………………… 3-19
22) Inspection of Thermostat ………………… 3-20
23) Inspection of Cooling Water Passages…… 3-21
24) Greasing Points …………………………… 3-22
4. Fuel System (Carburetor)
1 Special Tool ………………………………… 4-2
2 Parts Layout ………………………………… 4-3
Fuel Tank ……………………………………… 4-3
Carburetor ……………………………………… 4-4
3 Inspection Items …………………………… 4-5
1) Inspection of Fuel Feed System Piping …4-5
2) Draining Fuel………………………………… 4-6
3)
Inspection of Fuel Tank and Fuel Tank Cap
…4-7
4) Inspection of Fuel Cock …………………… 4-7
5) Inspection of Fuel Filter …………………… 4-7
6) Inspection of Carburetor …………………… 4-8
7) Assembling of Carburetor ………………… 4-9
8) Assembling Carburetor …………………… 4-10
9) Adjustment of Throttle Cable ……………… 4-11
10) Inspection of Idle Engine Speed ………… 4-12
11) Adjustment of Idle Engine Speed ………… 4-12
5.Power Unit
1 Special Tools ……………………………… 5-2
2 Parts Layout ………………………………… 5-3
Engine …………………………………………… 5-3
Recoil Starter …………………………………… 5-4
Oil Pan…………………………………………… 5-5
Cylinder ………………………………………… 5-6
Cam Shaft & Valve …………………………… 5-7
Piston & Crank Shaft…………………………… 5-8
3 Inspection Items …………………………… 5-9
1) Inspection of Compression Pressure …… 5-9
2) Inspection of Valve Clearance …………… 5-10
3) Removing Power Unit ……………………… 5-12
4) Removal and Disassembly of Crank Case Head …5-13
5) Inspection of Crank Case Head…………… 5-14
6) Assembly of Crank Case Head …………… 5-14
7) Installation of Crank Case Head ………… 5-14
8) Disassembly of Power Unit………………… 5-15
9) Removal of Rocker Arm …………………… 5-17
10) Inspection of Rocker Arm and Pivot ……… 5-18
11) Inspection of Push Rod Plate……………… 5-18
12) Inspection of Push Rod …………………… 5-18
13) Disassembly of Cylinder Block …………… 5-19
14) Inspection of Slinger (Splash Lubrication) …5-20
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iv 4st 2/2.5/3.5 2007
15) Inspection of Lifter ………………………… 5-20
16) Inspection of Cam Shaft …………………… 5-21
17) Inspection of Piston Outer Diameter……… 5-22
18) Inspection of Cylinder Inner Diameter …… 5-22
19) Inspection of Piston Clearance …………… 5-22
20) Inspection of Piston Ring Side Clearance …5-23
21) Inspection of Piston Rings ………………… 5-23
22) Inspection of Piston Pin …………………… 5-24
23) Inspection Connecting Rod Small End Inner Diameter …5-24
24) Inspection of Connecting Rod Big End Inner Diameter …5-24
25) Inspection of Connecting Rod Big End Side Clearance …5-25
26) Inspection of Crank Shaft ………………… 5-25
27) Disassembly and Assembly of Crank Shaft …5-26
28) Inspection of Crank Pin Oil Clearance …… 5-27
29) Installation of Piston and Connecting Rod …5-28
30) Removal of Valves and Springs…………… 5-29
31) Inspection of Valve Springs ……………… 5-29
32) Inspection of Valve ………………………… 5-30
33) Inspection of Valve Guide ………………… 5-30
34) Inspection of Valve Seat …………………… 5-31
35) Correction of Valve Seat…………………… 5-32
36) Installation of Valves ……………………… 5-35
37) Assembly of Cylinder and Crank Case…… 5-36
38) Assembly to Power Unit …………………… 5-39
39) Assembly of Rocker Arm ………………… 5-40
40) Assembly of Power Unit …………………… 5-41
41) Disassembly of Recoil Starter …………… 5-42
42) Inspection of Recoil Starter ……………… 5-42
43) Assembly of Recoil Starter ………………… 5-43
6.Lower Unit
1 Special Tools ……………………………… 6-2
2 Parts Layout ………………………………… 6-3
Drive Shaft Housing & Gear Case …………… 6-3
Gear Case (Drive Shaft) ……………………… 6-4
Gear Case (Propeller Shaft) ………………… 6-5
Shift ……………………………………………… 6-6
3 Inspection Item …………………………… 6-7
1) Draining Gear Oil …………………………… 6-7
2) Removing Propeller ………………………… 6-7
3) Removing Lower Unit ……………………… 6-8
4) Disassembly of Water Pump ……………… 6-8
5) Inspection of Water Pump ………………… 6-9
6) Removing Propeller Shaft Housing Ass'y 6-10
7) Disassembly of Propeller Shaft Ass'y …… 6-10
8) Inspection of Propeller Shaft ……………… 6-10
9) Assembly of Propeller Shaft Ass'y ……… 6-11
10) Disassembly of Propeller Shaft Housing …6-11
11) Inspection of Propeller Shaft Housing …… 6-11
12) Assembly of Propeller Shaft Housing …… 6-12
13) Removing Pump Case (Lower) …………… 6-12
14) Disassembly of Pump Case (Lower)……… 6-13
15) Assembly of Pump Case (Lower) ………… 6-13
16) Removing Clutch Cam and Cam Rod …… 6-13
17) Disassembly of Clutch Cam and Cam Rod 6-13
18) Inspection of Clutch Cam and Cam Rod …6-13
19) Assembly of Clutch Cam and Cam Rod …6-13
20) Removing Drive Shaft ……………………… 6-14
21) Disassembly of Drive Shaft ……………… 6-14
22) Inspection of Drive Shaft…………………… 6-14
23) Inspection of Forward Gear and Pinion Gear
(A and B Gears) ……………………………… 6-15
24) Assembly of Drive Shaft …………………… 6-15
25) Disassembly of Gear Case………………… 6-16
26) Inspection of Gear Case …………………… 6-17
27) Assembly of Gear Case …………………… 6-17
28) Installation of Clutch Cam and Cam Rod…6-18
29) Installation of Forward Gear and Pinion Gear
(A and B Gears) ……………………………… 6-18
30) Installation of Pump Case (Lower) ……… 6-18
31) Installation of Water Pump ………………… 6-19
32) Installation of Propeller Shaft Housing …… 6-20
33) Filling with Gear Oil ………………………… 6-21
34) Installation of Lower Unit…………………… 6-21
7.Bracket
1 Parts Layout ………………………………… 7-2
Clamp Bracket & Swivel Bracket……………… 7-2
Drive Shaft Housing & Gear Case …………… 7-3
Shift ……………………………………………… 7-4
Tiller Handle & Throttle ………………………… 7-5
Cowl ……………………………………………… 7-6
2 Assembling Procedure…………………… 7-7
1) Assembly of Clamp Bracket ……………… 7-7
2) Installation of Steering Stopper …………… 7-7
3) Installation of Drive Shaft Housing ……… 7-8
4) Installation of Water Pipe ………………… 7-8
5) Installation of Tiller Handle ………………… 7-9
6) Adjustment of Throttle Cable ……………… 7-10
8.Electrical System
1 Special Tools ……………………………… 8-2
2 Parts Layout ………………………………… 8-3
Magneto ………………………………………… 8-3
3 Ignition System and Ignition Control System … 8-4
1) Inspection of Ignition Spark ……………… 8-4
2) Inspection of Plug Cap …………………… 8-5
3) Inspection of Igniter ………………………… 8-6
4) Inspection of Stop Switch ………………… 8-7
9.Troubleshooting
1 Troubleshooting List……………………… 9-2
2 Power Unit …………………………………… 9-3
Trouble 1 Engine will not start or is a little hard to start.
(Recoil starter operates normally.) ……… 9-3
Trouble 2 Engine starts but stalls soon. …9-5
Fuel System………………………… 9-5
Ignition System …………………… 9-6
Compression Pressure …………… 9-7
Trouble 3 Idle engine speed will not stabilize. …9-8
Trouble 4 Rough acceleration.……………… 9-9
Trouble 5 Gear shifting cannot be made normally. …9-10
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v
4st 2/2.5/3.5 2007
1Service Information
2Service Data
3Maintenance
4Fuel System (Carburetor)
5Power Unit
6Lower Unit
7Bracket
8Electrical System
9Troubleshooting
INDEX
O K
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1
Service Information
1
1
Identification (Engine Serial Number)
…… 1-2
2 Securing of work safety …………… 1-2
1) Fire Prevention …………………………… 1-2
2) Ventilation ………………………………… 1-2
3) Protection ………………………………… 1-2
4) Genuine Parts …………………………… 1-2
5) Tools ……………………………………… 1-3
6) Recommendations on Service ………… 1-3
7) Cautions in Disassembling and
Assembling Components ……………… 1-4
3 Tools and Instruments ………………… 1-5
1) Test Propeller …………………………… 1-5
2) Instruments ……………………………… 1-5
3) List of Special Tool ……………………… 1-6
4 Predelivery Inspection ………………… 1-7
1) Steering Handle ………………………… 1-7
2) Gear Shift ………………………………… 1-7
3) Engine Oil ………………………………… 1-7
4) Gear Oil …………………………………… 1-7
5) Fuel Tank and Fuel Line ………………… 1-8
6) Rigging …………………………………… 1-8
7) Inspection of Tilt Stopper………………… 1-8
8) Inspection of Stop Switch ……………… 1-9
9) Cooling Water Check Port ……………… 1-9
10) Idle Operation …………………………… 1-9
11) Propeller Selection ……………………… 1-10
12)
Inspection of Forward and Reverse Shifts …1-10
5 Break-in Operation ……………………… 1-11
6 Test Run ……………………………………… 1-11
7 Checks After Test Run ………………… 1-12
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1-2
Service Information
4st 2/2.5/3.5 2007
1. Identification (Engine Serial Number)
Engine serial number is stamped on the swivel bracket of
outboard motor body.
2. Securing of work safety
1) Fire Prevention
Gasoline is hazardous material and very flammable. Do not
handle gasoline near ignition source such as spark or static
electricity.
2) Ventilation
Exhaust gas or gasoline vapor is hazardous for human
health. Be sure to ventilate well when working indoors.
3) Protection
Wear a pair of goggles, working gloves and safety shoes to
protect your body from chemicals and oils and eyes from
particles generated by grinding or polishing. Avoid contact
with oil, grease or sealing agent to the skin. In case of
exposure to such matters, wash away with soap and warm
water immediately.
4) Genuine Parts
Use parts and/or chemicals that are genuine items or
recommended.
Tokyo, Made inJapan
2006 Model
SERIAL No. XXXXXXXX
RATED POWER
FULL THROTTLE RANGE
MASS
5000
18 20 kg
6000 r / min
kW
3BR
12
3
F3.5A
1 Model Name
2 Model Type
3 Serial Number
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4st 2/2.5/3.5 2007
1
5) Tools
Use specified special tools to prevent damage to parts and
to perform work safely and correctly. Be sure to follow
installation procedures described in this manual and use
tightening torque specified.
6) Recommendations on Service
Remove foreign substances and dirt from outboard motor
and individual parts by cleaning. Apply recommended oil or
grease to rotating areas and sliding surfaces. Always
perform verifications such as ensuring smooth movement
and sealing.
1-3
3R0728150
3AC728710
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1-4
Service Information
4st 2/2.5/3.5 2007
LIT
GREASE
LIT
110
ø66~ø70 hole
50
200
66
PowerUnitWorkTable (mm)
35
45
200
7) Cautions in Disassembling and
Assembling Components
(1) Secure outboard motor to dedicated stand firmly.
(2) Take special care not to scratch painted surface or mating
surfaces of cylinder and crankcase.
(3) Replace unreusable parts such as packings, gaskets, O
rings, oil seals, spring pins or split pins with new ones after
they were removed. Replace deformed snap rings with new
ones.
(4) When replacing parts, be sure to use genuine parts. For
fluids such as gear oil, use genuine product.
(5) Be sure to use special tools that are specified, and perform
the work properly.
(6) When reassembling parts, use their mating marks. For parts
without mating marks, simple marking makes reassembling
easier. Use applicable parts list for reference. Refer to
applicable parts list.
(7) Clean individual parts that have been removed, and check
their condition.
(8) When reassembling parts, take sufficient care also for details
such as fit, repair limits, air tightness, cleanliness of oil holes
for lubrication and greasing, packings, wirings and piping.
For components using many bolts and nuts for assembling,
such as cylinder head and crankcase, tighten all the
fasteners evenly to their specified torque clockwise in two or
three stages, inner ones first and then outer ones. (Reverse
the order when disassembling.)
(9) When installing bearings, bring the flat (numbered) side of
the component to the special assembling tool.
(10) When installing oil seals, be careful not to scratch the
surface of the lip that contacts with the shaft, and install them
in correct orientation. Apply recommended grease to the lip
before installation.
(11) When applying liquid packing, take sufficient care of the
thickness and quantity. Excessive application may ooze out,
adversely affecting interior of the crankcase. Use adhesive
after thoroughly reading the instructions.
(12) When servicing power unit, use of wooden work board
makes the work easier.
6
8
7
1
14
4
4
3
2
18
16
16
Fig.3-7
1-1
1-2
1-2
1-2
1-2
1-1
1-1
1-3
1-4
1-4
1-3
1-2
5
5
54
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1-5
1
4st 2/2.5/3.5 2007
2) Instruments
For the following measuring instruments, use commercially available ones.
Circuit tester (Resistance : 1Ω, 10Ω, 10 kΩ, AC voltage : 30 - 300V, DC voltage : 30V)
Vernier calipers (JIS B 7507 : M1 type, 300 mm)
Micrometer (JIS B 7502 : minimum graduation of 0.01 mm, outer, 0 - 25 mm, 25 - 50 mm, 50 - 75 mm)
Cylinder gauge (JIS B 7515 : 4 - 6 mm, 10 - 25 mm, 25 - 50 mm, 50 - 75 mm)
Ring gauge (JIS B 7420 : ø5.5, ø14, ø20, ø47, ø55)
Dial gauge (JIS B 7503 : minimum graduation of 0.01 mm)
Thickness gauge (JIS B 7524 : 0.03 - 0.3 mm)
V block (JIS B 7540)
Surface plate (JIS B 7513 : 500 mm x 500 mm)
Dial gauge magnet base or dial gauge stand
Model Speed at WOT
(Wide Open Throttle) (r/min)
F2A/F2.5 A 4,500 -5,500
F3.5 A 5,000 -6,000
3. Tools and Instruments
1) Test Propeller
P/N. 3AB-64111-0
Outer diameter :120mm
Width :16mm
(Reference value)
This test propeller has been designed for break-
in operation and load test operation.
The engine speed at WOT varies depending on
the conditions such as the level or water or air
temperature, and thus, the measurement is not
for confirmation or power of the engine.
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Spark Tester
P/N. 3F3-72540-0
Inspecting sparks
Removing flywheel
Flywheel Puller Kit
P/N. 3C7-72211-1
Removing or installing valve
springs
Measuring compression
pressure
Valve Spring Compressor Attachment
P/N. 3AB-99076-0
Compression Gauge
P/N. 3AC-99030-0
Removing bearings
Universal Puller Plate
P/N. 3AC-99750-0
Removing or installing
flywheel
Flywheel Holder
P/N. 3AC-99200-0
Measuring engine revolution
speed
Tachometer
P/N. 3AC-99010-0
Thickness Gauge
P/N. 353-72251-0
Installing spring pin
Spring Pin Tool B
P/N. 345-72228-0
Measuring gaps
Removing spring pin
Spring Pin Tool A
P/N. 345-72227-0
1-6
Service Information
4st 2/2.5/3.5 2007
3) List of Special Tool
3B7-72783-0 3B7-72784-0
Driver Rod 3
P/N. 3AB-99702-0
Used in combination with center plate and
bearing attachment
Used in combination with driver rod and
bearing attachment to locate lower gear
case bearing
Center Plate 3
P/N. 3AB-99701-0
Installing drive shaft bearing.
Bearing Install Tool 2
P/N. 3AB-99900-0
Bearing Attachment 2
P/N. 3BR-99905-0
Installing bearings
Bearing Attachment 3
P/N. 3AB-99905-0
Used in combination with driver rod and
center plate to locate lower gear case
bearing
Bearing Attachment 4
P/N. 3BV-99905-0
Installing bearings
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1-7
1
4st 2/2.5/3.5 2007
1
å ∫
ç∂
ab
cc
dd
c
d
Lighter
Heavier
300cm3
250cm3
1
4st OIL
4st
OIL
4. Predelivery Inspection
1) Steering Handle
åCheck installations for tension and play.
∫Adjust steering friction.
çCheck throttle grip for movement.
(Fully Open a/ Fully Closed b)
∂Adjust throttle friction.
2) Gear Shift
1. Check shift lever 1and propeller shaft for smooth
movement of the shift between forward (F) and neutral (N)
while engine is operating.
3) Engine Oil
1. Set outboard motor straight ahead and vertical.
2. Fill with Engine Oil.
4 Stroke Engine Oil :
300cm3(10 fl.oz)
OIL
F
N
1
CAUTION
Engine oil is removed before shipment to
prevent leakage during transportation.
3. Use oil level gauge to check oil quantity.
(Straight ahead and vertical)
1
2
OIL
GEARGEAR
GEAR
4) Gear Oil
1. Check quantity of gear oil.
Gear Oil :
180cm3(6 fl.oz)
OIL
Spilling of oil from upper plug when removed
indicates that gear case is filled with specified
quantity of gear oil.
1Oil Filler Cap
1Oil Plug 2Gasket
1Steering Adjust Screw cLighter dHeavier
Do not reuse.
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1-8 4st 2/2.5/3.5 2007
6) Rigging
1. Check that clamp bracket is fixed securely to hull.
2. Check location of anti-ventilation plate relative to boat
bottom, and, if necessary, adjust to prevent decrease in
performance force and engine overheating.
a
5) Fuel Tank and Fuel Line
1. Check that fuel tank contains sufficient amount of gasoline,
fuel line is connected and is free of leaks.
CAUTION
Since this is a 4 stroke engine model, do
not use fuel mixed with engine oil. Use of
fuel mixed with engine oil will cause engine
trouble.
7) Inspection of Tilt Stopper
1. Fully tilt up the outboard motor 1, lock with the tilt stopper
2, and then check that the holding mechanism functions
normally.
2
1
Test-run to determine the best installation
height.
a30 - 50 mm ( 1.2 - 2.0 in )
Location of anti-ventilation plate : Standard value
30 - 50 mm (1.2 - 2.0in) from boat bottom
Service Information
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8) Inspection of Stop Switch
1. Press stop switch 1hard or pull out lock 2from stop switch
1to check that engine stops.
2
1
2
1
10) Idle Operation
1. After engine has warmed up in neutral, use tachometer to
check idle engine speed is as specified.
1
Idle Engine Speed :
1,250 - 1,350 r/min
RPM
9) Cooling Water Check Port
1. Check that cooling water check port 1discharges water
during engine runs.
1
Tachometer :
P/N. 3AC-99010-0
1High Tension Cord
· Use tachometer to measure after warm up
operation.
· Set the measurement mode to 4 stroke 2
cylinder · 2 stroke 1 cylinder.
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1-10 4st 2/2.5/3.5 2007
Service Information
11) Propeller Selection
1. Select a propeller that is best-suited to type of boat and
application.
CAUTION
Incorrect-selection of propeller can cause
adverse effects on engine life, fuel
consumption, etc. as well as on performance.
Range of operating engine revolution at WOT
F2/2.5 : 4,500 - 5,500r/min
F3.5 : 5,000 - 6,000r/min
RPM
Propeller [Marking]
No. of Blades x
Diameter x Pitch
in (mm)
［I 7］3 x 7 x 7 (3 x 188 x 178) Plastic Standard
［F6/B6］3 x 7 x 6 (3 x 188 x 145) Plastic/Aluminum Option
［］ 3 x 7 x 4.5 (3 x 188 x 110) Plastic Option
38
／
38
／
38
／
12) Inspection of Forward and Reverse Shifts
Use shift lever 1to shift the gear to forward (F) and Neutral (N).
1
2
3
N
F
a
In reverse operation, run at low speed, and do
not increase the engine speed unnecessarily.
1. Forward
Return handle grip 2to idle speed a, and then, move shift
lever 1toward the operator (F) quickly.
2. Reverse
In the same way as forward shift inspection, set the engine to
idle speed, shift into 1to neutral (N), put up handle 3, turn
outboard motor 180 degrees, and then, shift into forward (F)
quickly.
3. Shallow water run
In shallow water, run at the lowest possible speed while
watching the depth and obstacles.
WARNING
Shifting at high engine speed may cause
fall of passenger due to abrupt acceleration
and damage to gear, clutch and other
components of the outboard motor. Shift at
the lowest engine speed.
CAUTION
Shear pin is designed to be broken when
the propeller receives damaging impact.
However, it may be broken when shifting at
high engine speed because of high shear
stress applied to the pin.
3
1Shift Lever
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6. Test Run
1. Start engine and check if shifting is smooth.
2. After completing warm-up operation, check idle engine
speed.
Complete test run during break-in operation.
Trolling Engine Speed :
1,150 - 1,250 r/min
RPM
4. Run at 3,000 r/min or half of WOT for initial 2 hours, then at
4,000 r/min or 3/4 of WOT for 1 hour.
5. Check that shifting into reverse will not tilt up outboard motor
and allow water to run into boat.
3. Shift gear into forward (F) and run at idle speed
(for approximately 10 minutes).
1
1High Tension Cord
Idle Engine Speed :
1,250 - 1,350 r/min
RPM
Tachometer :
P/N. 3AC-99010-0
5. Break-in Operation
Break-in operation is needed to smooth sliding surfaces
between components such as pistons and cylinder, piston
rings, piston pins, crank shaft, connecting rods, and intake
and exhaust valves.
Operation Dead Slow or Idling
1/2 of WOT or less at
approximately 3,000
r/min
3/4 of WOT or less at
approximately 4,000
r/min
WOT run for approximately 1
minute can be included every
10 minutes of run.
WOT run for approximately 2
minute can be included every
10 minutes of run.
Running at the slowest
possible speed
3/4 of WOT at
approximately 4,000
r/min
Regular Operation
Time 0 10 minutes 2 hours 3 hours 10 hours
Break-in Operation…10 hours
· Use tachometer to measure after warm up
operation.
· Set the measurement mode to 4 stroke 2
cylinder · 2 stroke 1 cylinder.
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1-12 4st 2/2.5/3.5 2007
Service Information
7. Checks After Test Run
1. Check that power unit, lower unit and bracket are free of
looseness or play.
2. Check that no water is present in gear oil.
3. Check that no fuel leakage exists in the cowl.
4. Check that no oil and water leak in the cowl and no water is
present in engine oil.
5. If using in salt water after test run, use flushing attachment
1(optional) and fresh water to wash cooling water path by
idling engine.
1
1
1Flushing Attachment (optional)
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2
2
Service Data
1 Outline Dimensons ……………………… 2-2
1）Engine Dimensions ……………………… 2-2
2）Clamp Dimensions ……………………… 2-3
2 Cooling Water System Diagram……… 2-4
3 Wiring Diagram …………………………… 2-5
4 Specifications ……………………………… 2-6
5 Maintenance Data………………………… 2-8
6 Tightening Torque Data ………………… 2-12
7 Sealant Application Locations ……… 2-14
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2-2
Service Data
4st 2/2.5/3.5 2007
O
N
M
HG
D
F
L
C
B
KJ
P
I
E
OIL LEVE
O I L
A
Item Type Unit mm in
A mm/in 377 14.84
S mm/in 649 25.55
BL mm/in 776 30.55
S mm/in 435 17.13
CL mm/in 562 22.13
D mm/in 446 17.56
E mm/in 108 4.25
F mm/in 354 13.94
G mm/in 336 13.23
H mm/in 303 11.93
I mm/in 58 2.28
J mm/in 208 8.19
K mm/in 628 24.72
L mm/in 363 14.29
M mm/in 340 13.39
N mm/in 276 10.87
O mm/in 453 17.83
P deg. 65
1.Outline Dimensons
1）Engine Dimensions
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