9-1
TROUBLESHOOTING
EAS28450
TROUBLESHOOTING
EAS28460
GENERAL INFORMATION
NOTE:
The following guide for troubleshooting does
not cover all the possible causes of trouble. It
should be helpful, however, as a guide to basic
troubleshooting. Refer to the relative procedure
in this manual for checks, adjustments, and re-
placement of parts.
EAS28470
STARTING FAILURES
Engine
1. Cylinder and cylinder head
• Loose spark plug
• Loose cylinder head or cylinder
• Damaged cylinder head gasket
• Damaged cylinder gasket
• Worn or damaged cylinder
• Incorrect valve clearance
• Improperly sealed valve
• Incorrect valve-to-valve-seat contact
• Incorrect valve timing
• Faulty valve spring
• Seized valve
2. Piston and piston ring(s)
• Improperly installed piston ring
• Damaged, worn or fatigued piston ring
• Seized piston ring
• Seized or damaged piston
3. Air filter
• Improperly installed air filter
• Clogged air filter element
4. Crankcase and crankshaft
• Improperly assembled crankcase
• Seized crankshaft
Fuel system
1. Fuel tank
• Empty fuel tank
• Clogged fuel tank drain hose
• Deteriorated or contaminated fuel
2. Fuel pump
• Faulty fuel pump
• Faulty relay unit
3. Throttle body
• Deteriorated or contaminated fuel
• Sucked-in air
Electrical system
1. Battery
• Discharged battery
• Faulty battery
2. Fuse(s)
• Blown, damaged or incorrect fuse
• Improperly installed fuse
3. Spark plug
• Incorrect spark plug gap
• Incorrect spark plug heat range
• Fouled spark plug
• Worn or damaged electrode
• Worn or damaged insulator
• Faulty spark plug cap
4. Ignition coil
• Cracked or broken ignition coil body
• Broken or shorted primary or secondary coils
• Faulty spark plug lead
5. Ignition system
• Faulty ECU
• Faulty crankshaft position sensor
• Broken A.C. magneto rotor woodruff key
6. Switches and wiring
• Faulty main switch
• Faulty engine stop switch
• Broken or shorted wiring
• Faulty neutral switch
• Faulty start switch
• Faulty sidestand switch
• Faulty clutch switch
• Improperly grounded circuit
• Loose connections
7. Starting system
• Faulty starter motor
• Faulty starter relay
• Faulty starting circuit cut-off relay
• Faulty starter clutch
EAS28490
INCORRECT ENGINE IDLING SPEED
Engine
1. Cylinder and cylinder head
• Incorrect valve clearance
• Damaged valve train components
2. Air filter
• Clogged air filter element
Fuel system
1. Throttle body
• Damaged or loose throttle body joint
• Improperly adjusted engine idling speed
(throttle stop screw)
• Improper throttle cable free play
• Flooded throttle body
• Faulty air induction system
Summary of Contents for XT660Z 2008
Page 1: ...SERVICE MANUAL 2008 11D F8197 E0 XT660Z ...
Page 8: ......
Page 24: ......
Page 44: ...2 20 TIGHTENING TORQUES Cylinder head tightening sequence 2 4 3 1 ...
Page 54: ...2 30 COOLING SYSTEM DIAGRAMS 1 2 3 4 5 6 7 9 10 11 12 5 8 11 A ...
Page 57: ...2 33 LUBRICATION DIAGRAMS LUBRICATION DIAGRAMS 1 A A A A B B B A A B 3 2 2 4 1 1 5 5 ...
Page 59: ...2 35 LUBRICATION DIAGRAMS A A A A 3 1 2 3 4 ...
Page 60: ...2 36 LUBRICATION DIAGRAMS 1 Oil delivery pipe 2 2 Oil delivery pipe 1 3 Oil filter 4 Oil pump ...
Page 61: ...2 37 LUBRICATION DIAGRAMS 1 7 2 3 4 5 6 A ...
Page 63: ...2 39 LUBRICATION DIAGRAMS 1 6 5 4 3 2 ...
Page 65: ...2 41 CABLE ROUTING CABLE ROUTING ...
Page 67: ...2 43 CABLE ROUTING ...
Page 69: ...2 45 CABLE ROUTING ...
Page 71: ...2 47 CABLE ROUTING ...
Page 73: ...2 49 CABLE ROUTING ...
Page 75: ...2 51 CABLE ROUTING ...
Page 77: ...2 53 CABLE ROUTING ...
Page 79: ...2 55 CABLE ROUTING ...
Page 81: ...2 57 CABLE ROUTING ...
Page 83: ...2 59 CABLE ROUTING ...
Page 176: ...4 56 FRONT FORK WARNING Make sure the brake hoses are routed prop erly 1 2 3 ...
Page 270: ......
Page 284: ......
Page 301: ...7 17 FUEL INJECTION SYSTEM WIRING DIAGRAM ...
Page 324: ......
Page 327: ...8 1 IGNITION SYSTEM EAS27090 IGNITION SYSTEM EAS27110 CIRCUIT DIAGRAM ...
Page 331: ...8 5 ELECTRIC STARTING SYSTEM EAS27160 ELECTRIC STARTING SYSTEM EAS27170 CIRCUIT DIAGRAM ...
Page 337: ...8 11 CHARGING SYSTEM EAS27200 CHARGING SYSTEM EAS27210 CIRCUIT DIAGRAM ...
Page 338: ...8 12 CHARGING SYSTEM 2 A C magneto 5 Rectifier regulator 7 Battery 8 Main fuse ...
Page 340: ...8 14 CHARGING SYSTEM ...
Page 341: ...8 15 LIGHTING SYSTEM EAS27240 LIGHTING SYSTEM EAS27250 CIRCUIT DIAGRAM ...
Page 345: ...8 19 SIGNALING SYSTEM EAS27270 SIGNALING SYSTEM EAS27280 CIRCUIT DIAGRAM ...
Page 351: ...8 25 COOLING SYSTEM EAS00807 COOLING SYSTEM CIRCUIT DIAGRAM ...
Page 354: ...8 28 COOLING SYSTEM ...
Page 355: ...8 29 IMMOBILIZER SYSTEM ET5YU1002 IMMOBILIZER SYSTEM ET5YU1003 CIRCUIT DIAGRAM ...
Page 364: ...8 38 IMMOBILIZER SYSTEM ...
Page 365: ...8 39 ELECTRICAL COMPONENTS EAS27970 ELECTRICAL COMPONENTS ...
Page 367: ...8 41 ELECTRICAL COMPONENTS ...
Page 369: ...8 43 ELECTRICAL COMPONENTS EAS27980 CHECKING THE SWITCHES ...
Page 388: ......
Page 390: ......
Page 396: ...COLOR CODE ...
Page 397: ......
Page 398: ...YAMAHA MOTOR ITALIA S P A ...
Page 399: ...XT660Z 2008 WIRING DIAGRAM ...