Yamaha MZ360 User manual

SERVICE MANUAL
MZ360
MX360
MZ400
7HC-F8197-E1
2019.03×1 !
7HC-F8197-E1_cover.indd 1-2 2019/03/13 10:20:44

7HC-F8197-E1_cover.indd 3-4 2019/03/13 10:20:44

MZ360/MX360/MZ400
SERVICE MANUAL
©2018 by Yamaha Motor Powered
Products Co., Ltd.
1st Edition, March 2019
All rights reserved. Any reprinting or
unauthorized use without the written
permission of Yamaha Motor
Powered Products Co., Ltd.
is expressly prohibited.

IMPORTANT
This manual was produced by the Yamaha Motor Powered Products Co., Ltd. primarily for use by
Yamaha dealers and their qualified mechanics. It is not possible to include all the knowledge of a
mechanic in one manual. Therefore, anyone who uses this book to perform maintenance and
repairs on Yamaha machines should have a basic understanding of mechanics and the techniques
to repair these types of machines. Repair and maintenance work attempted by anyone without this
knowledge is likely to render the machine unsafe and unfit for use.
Yamaha Motor Powered Products Co., Ltd. is continually striving to improve all of its models. Modifi-
cations and significant changes in specifications or procedures will be forwarded to all authorized
Yamaha dealers and will appear in future editions of this manual where applicable.
TIP
Designs and specifications are subject to change without notice.
IMPORTANT MANUAL INFORMATION
Particularly important information is distinguished in this manual by the following notations.
This is the safety alert symbol. It is used to alert you to potential personal injury hazards.
Obey all safety messages that follow this symbol to avoid possible injury or death.
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 damage to the machine
or other property.
TIP
A TIP provides key information to make procedures easier or clearer.
WARNING
NOTICE

HOW TO USE THIS MANUAL
This manual is intended as a handy, easy-to-read reference book for the mechanic.
Comprehensive explanations of all installation, removal, disassembly, assembly, repair and check
procedures are laid out with the individual steps in sequential order.
• The manual is divided into chapters and each chapter is divided into sections. The current section
title is shown at the top of each page “1”.
• Sub-section titles appear in smaller print than the section title “2”.
• To help identify parts and clarify procedure steps, there are exploded diagrams at the start of each
removal and disassembly section “3”.
• Numbers are given in the order of the jobs in the exploded diagram. A number indicates a disas-
sembly step “4”.
• Symbols indicate parts to be lubricated or replaced “5”.
Refer to SYMBOLS.
• A job instruction chart accompanies the exploded diagram, providing the order of jobs, names of
parts, notes in jobs, etc. “6”. This step explains removal procedure only. For installation, reverse
the steps.
• Jobs requiring more information (such as special tools and technical data) are described sequen-
tially “7”.
1
3
7
2
5
4
6

SYMBOLS
The following symbols are used in this manual for easier understanding.
TIP
The following symbols are not relevant to every machine.
SYMBOL DEFINITION SYMBOL DEFINITION
Filling fluid Lubricant
Special tool Tightening torque
Wear limit, clearance Engine speed
Electrical data Replace the part with a new one.
Lithium-soap base grease Molybdenum disulfide grease
Engine oil Silicone fluid
Apply locking agent (LOCTITE®)
T
R
.
.
New
LS
M
E
S
LT

GENERAL INFORMATION
PERIODIC CHECKS AND
ADJUSTMENTS
ENGINE
CARBURETOR
ELECTRICAL
TROUBLESHOOTING
SPECIFICATIONS
1
2
3
4
5
6
7
8
9
10
INDEX

TABLE OF CONTENTS
GENERAL INFORMATION
MACHINE IDENTIFICATION...................... 1-1
SERIAL NUMBER ................................. 1-1
MODEL NAME AND CODE .................. 1-1
DIMENSIONS ............................................. 1-2
DIMENSION CHART............................. 1-2
TOP ....................................................... 1-4
MOUNTING BASE ................................ 1-6
LEFT SIDE ............................................ 1-7
FRONT .................................................. 1-8
RIGHT SIDE........................................ 1-10
IMPORTANT INFORMATION ................... 1-11
PREPARATION FOR REMOVAL 
AND DISASSEMBLY ........................... 1-11
CAUTION ON SERVICE ..................... 1-11
NOTES ON SERVICE ......................... 1-11
ALL REPLACEMENT PARTS.............. 1-12
GASKETS, OIL SEALS, AND 
O-RINGS ............................................. 1-12
BEARINGS AND OIL SEALS.............. 1-13
BASIC SERVICE INFORMATION ............ 1-13
ELECTRICAL SYSTEM ...................... 1-13
SPECIAL TOOLS AND TESTERS........... 1-17
PERIODIC CHECKS AND
ADJUSTMENTS
INTRODUCTION ........................................ 2-1
MAINTENANCE INTERVALS CHART ....... 2-1
PERIODIC MAINTENANCE/
LUBRICATION INTERVALS....................... 2-1
PERIODIC MAINTENANCE ....................... 2-3
SPARK PLUG........................................ 2-3
FUEL LEAKAGE ................................... 2-4
ENGINE OIL LEAKAGE ........................ 2-4
ENGINE OIL LEVEL.............................. 2-4
REPLACING THE ENGINE OIL............ 2-5
AIR FILTER ELEMENT 
(MZ360/MZ400)..................................... 2-6
AIR FILTER ELEMENT (MX360)........... 2-7
MUFFLER (Equipped models) .............. 2-8
FUEL TANK FILTER 
(Equipped models)...............................2-10
FUEL COCK STRAINER .....................2-11
BREATHER HOSE ..............................2-12
CYLINDER HEAD 
DECARBONIZATION...........................2-12
ADJUSTING THE VALVE 
CLEARANCE.......................................2-12
ENGINE SPEED (No throttle lever 
models) ................................................2-15
ENGINE SPEED (Throttle lever 
equipped models) ................................2-15
ADJUSTING THE ENGINE SPEED 
(No throttle lever models).....................2-16
ADJUSTING THE ENGINE SPEED
(Throttle lever equipped models) .........2-17
RECOIL STARTER ..............................2-18
FITTINGS AND FASTENERS..............2-19
ENGINE
ENGINE INSPECTION................................3-1
MEASURING THE COMPRESSION
PRESSURE ...........................................3-1
AIR FILTER .................................................3-3
MZ360/MZ400 .......................................3-3
MX360 ...................................................3-4
FUEL TANK (Equipped models) ...............3-5
EXCEPT FOR MX360C46A5 ................3-5
MX360C46A5 ........................................3-6
MUFFLER ...................................................3-7
EQUIPPED MODELS ............................3-7
INSTALLING THE MUFFLER ................3-8
RECOIL STARTER .....................................3-9
MZ360/MZ400 .......................................3-9
DISASSEMBLING THE RECOIL
STARTER (MZ360/MZ400)..................3-10
CHECKING THE RECOIL STARTER
(MZ360/MZ400) ...................................3-10
ASSEMBLING THE RECOIL 
STARTER (MZ360/MZ400)..................3-11
MX360 .................................................3-13
DISASSEMBLING THE RECOIL
STARTER (MX360)..............................3-14

CHECKING THE RECOIL STARTER
(MX360)............................................... 3-14
ASSEMBLING THE RECOIL 
STARTER (MX360) ............................. 3-15
FLYWHEEL............................................... 3-17
MZ360/MZ400 ..................................... 3-17
MX360 ................................................. 3-18
REMOVING THE FLYWHEEL ............. 3-19
INSTALLING THE FLYWHEEL............ 3-20
INSTALLING THE TCI UNIT ............... 3-20
GOVERNOR ............................................. 3-22
THROTTLE LEVER ASSEMBLY
(MX360BA6A0) ................................... 3-22
THROTTLE LEVER ASSEMBLY
(MX360C46A5/MX360AA6A0/
MX360AA6A5/MX360AA6A6) ............. 3-23
GOVERNOR ARM ASSEMBLY
(MX360KA6D0 for KOR) ..................... 3-24
GOVERNOR ARM ASSEMBLY 
(MZ360/MZ400/MX360KA6D0 
except for KOR) ................................... 3-25
FLYWEIGHT SHAFT ASSEMBLY 
(MZ360/MZ400)................................... 3-26
FLYWEIGHT SHAFT ASSEMBLY 
(MX360)............................................... 3-27
REMOVING THE FLYWEIGHT 
SHAFT ASSEMBLY AND 
GOVERNOR FORK............................. 3-28
DISASSEMBLING THE FLYWEIGHT
SHAFT ASSEMBLY............................. 3-28
CHECKING THE FLYWEIGHT 
SHAFT ASSEMBLY............................. 3-28
ASSEMBLING THE FLYWEIGHT 
SHAFT ASSEMBLY............................. 3-29
INSTALLING THE FLYWEIGHT 
SHAFT ASSEMBLY AND 
GOVERNOR FORK............................. 3-29
INSTALLING THE THROTTLE 
LEVER ASSEMBLY (Equipped 
models)................................................ 3-30
ADJUSTING THE GOVERNOR .......... 3-30
ENGINE SWITCH AND OIL WARNING 
UNIT.......................................................... 3-31
ENGINE SWITCH ............................... 3-32
CYLINDER HEAD COVER, CYLINDER
HEAD........................................................ 3-33
CHECKING THE ROCKER ARM........ 3-35
CHECKING THE PUSH ROD..............3-35
CHECKING THE CYLINDER HEAD ...3-35
INSTALLING THE CYLINDER HEAD
ASSEMBLY ..........................................3-36
VALVE .......................................................3-37
REMOVING THE VALVES AND 
VALVE SPRINGS.................................3-38
CHECKING THE VALVES AND 
VALVE SPRINGS.................................3-38
CHECKING THE VALVE SEATS .........3-40
VALVE LAPPING .................................3-42
INSTALLING THE VALVES AND 
VALVE SPRINGS.................................3-43
PISTON, CAMSHAFT, CRANKCASE, 
AND CRANKSHAFT.................................3-44
MZ360/MZ400 .....................................3-44
MX360 .................................................3-46
REMOVING THE BALANCER 
SHAFT, CAMSHAFT, AND VALVE 
LIFTER ................................................3-48
CHECKING THE BALANCER 
SHAFT .................................................3-48
CHECKING THE CAMSHAFT.............3-48
CHECKING THE VALVE LIFTER ........3-50
INSTALLING THE VALVE LIFTER,
BALANCER SHAFT, AND 
CAMSHAFT .........................................3-50
CHECKING THE CRANKCASE 
COVER ................................................3-50
INSTALLING THE CRANKCASE 
COVER ................................................3-51
CHECKING THE CYLINDER AND
PISTON................................................3-51
CHECKING THE CRANKCASE ..........3-53
CHECKING THE PISTON PIN ............3-53
CHECKING THE PISTON RINGS .......3-54
CHECKING THE CRANKSHAFT ........3-55
CHECKING THE CONNECTING 
ROD OIL CLEARANCE .......................3-56
INSTALLING THE PISTON AND 
PISTON RING......................................3-57
INSTALLING THE CRANKSHAFT.......3-57
SELECTING THE CRANKSHAFT 
SHIM....................................................3-59

CARBURETOR
REMOVING THE CARBURETOR .............. 4-1
MZ360/MZ400 ....................................... 4-1
MX360 ................................................... 4-2
DISASSEMBLING THE CARBURETOR ... 4-3
MZ360/MZ400 ....................................... 4-3
MX360 ................................................... 4-4
CHECKING THE CARBURETOR ......... 4-5
ELECTRICAL
CIRCUIT DIAGRAM ................................... 5-1
WITH STARTER MOTOR, OIL 
WARNING UNIT, OIL WARNING 
LIGHT.................................................... 5-1
WITH OIL WARNING UNIT, OIL 
WARNING LIGHT.................................. 5-3
WITHOUT OIL WARNING UNIT, OIL
WARNING LIGHT.................................. 5-5
ELECTRICAL COMPONENTS .................. 5-7
CHECKING THE SWITCH 
CONTINUITY ........................................ 5-8
CHECKING THE FUSE (Equipped 
models).................................................. 5-8
CHECKING THE IGNITION SPARK 
GAP..................................................... 5-10
CHECKING THE SPARK PLUG CAP
RESISTANCE...................................... 5-11
CHECKING THE AIR GAP.................. 5-11
CHECKING THE IGNITION COIL 
(TCI UNIT, PRIMARY) 
RESISTANCE...................................... 5-11
CHECKING THE IGNITION COIL 
(TCI UNIT, SECONDARY) 
RESISTANCE...................................... 5-12
CHECKING THE ENGINE SWITCH ... 5-13
CHECKING THE OIL LEVEL 
SWITCH .............................................. 5-13
CHECKING THE STARTER MOTOR
OPERATION (Equipped models) ........ 5-14
CHECKING THE WIRE HARNESS .... 5-14
ELECTRIC STARTING SYSTEM ............. 5-15
REMOVING THE STARTER MOTOR
(Equipped models) .............................. 5-15
DISASSEMBLING THE STARTER 
MOTOR (Equipped models).................5-16
CHECKING THE ARMATURE COIL....5-17
CHECKING THE BRUSH ....................5-18
CHECKING THE STARTER RELAY ....5-18
ASSEMBLING THE STARTER 
MOTOR................................................5-18
CHARGING SYSTEM ...............................5-19
CHECKING THE CHARGING COIL
(Equipped models)...............................5-19
TROUBLESHOOTING
ENGINE DOES NOT START ......................6-1
ELECTRIC STARTING SYSTEM 
(Equipped models) ....................................6-2
ENGINE STARTS BUT STALLS.................6-2
ENGINE SPEED DOES NOT 
INCREASE..................................................6-3
ENGINE SPEED IS UNEVEN .....................6-4
THE BATTERY IS NOT CHARGED
(Equipped models) ....................................6-4
GOVERNOR OPERATION..........................6-5
SPECIFICATIONS
GENERAL SPECIFICATIONS ....................7-1
MAINTENANCE SPECIFICATIONS ...........7-3
ENGINE .................................................7-3
ELECTRICAL.........................................7-7
TIGHTENING TORQUES............................7-8
GENERAL TORQUE 
SPECIFICATIONS.....................................7-10
LUBRICATION POINTS AND TYPE OF
LUBRICANTS ...........................................7-11
WIRE ROUTING DIAGRAM .....................7-12
UPPER SIDE VIEW (MZ360) ..............7-12
UPPER SIDE VIEW (MX360) ..............7-14
UPPER SIDE VIEW (MZ400) ..............7-16