2004 YAMAHA TT600RE fuel

CARBURETOR ASSEMBLY
6-16
CARB
FUEL LEVEL ADJUSTMENT (CARBURE-
TOR INSTALLED
1. Place the motorcycle on a level surface.
2. Make sure that the carburetor is in a horizon- tal position by placing a hydraulic jack under
the engine.
Fuel level gauge: P/N. 90890-01312
4. Loosen drain screw (2) and heat the engine.
5. Measure:
•Fuel level (a)
Out of specification ➔Adjust.
Fuel level: 6.0 ~ 8.0 mm
Under the edge of the carburetor
body.
6. Adjust:
•Fuel level
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
Fuel level adjustment:
•Remove carburetor assembly.
•Inspect valve seat and needle valve set.
•If either of the two is worn, replace both.
•If both are perfect, adjust float height by bend-
ing the wing tab of the float itself (1).
•Recheck the fuel level.
3. Connect the fuel level gauge (1) to the carbu- rettor nipple.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
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ELECIGNITION SYSTEM
7-13
DIAGNOSTICS IF THE IGNITION SYSTEM WERE TO STOP WORKING (NO OR INTERMITTENT SPARK)
Procedure
Check:
1. Fuse
2. Battery
3. Spark plug
4. Amplitude of ignition spark
5. Spark plug cap resistance
6. Ignition winding resistance 7. Main switch
8. Engine stop switch
9. Sidestand switch
10. Neutral switch
11. Clutch switch
12. Pick-up coil resistance
13. Wiring connections (whole connection sys- tem)
NOTE:
Before making the inspections mentioned, remove the following parts:
1. Seat
2. Rear cowling 3. Fuel tank
4. Cowling (headlight)
•To check functioning defects use the following special tools.
Dinamic spark tester: P/N. 90890-06754
Pocket tester:P/N. 90890-03112
1. Fuse
•Check the fuse for continuity.
Refer to “CHECKING THE FUSES” in
Chapter 3.
•Is the fuse OK?
YES
2. Battery
•Check the condition of the battery.
Refer to “CHECKING AND CHARGING
THE BATTERY” in Chapter 3.
Min. open-circuit voltage:
2.8 V or more at 20°C (68°F)
•Is the battery OK?
NO
Replace the fuse.
NO
•Clean the battery terminals.
•Recharge or replace the battery.
YES
*
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ELECTRICAL STARTING SYSTEM
7-24
ELEC
DIAGNOSTICS THE STARTER FAILS TO WORK
Procedure
Inspect:
(1) Fuse
(2) Battery
(3) Starting motor
(4) Starter relay
(5) Main switch (6) Engine stop switch
(7) Sidestand switch
(8) Neutral switch
(9) Clutch switch
(10) Starter switch
(11) Harness connections
NOTE:
Before starting inspections, remove the following parts:
1. Seat
2. Rear cowling 3. Fuel tank
4. Cowling (headlight)
•To check for defects use the following special tools.
Pocket tester: P/N. 90890-03112
1. Fuse.
•Remove fuse.
•Connect the pocket tester ( Ωx 1) to the
fuse.
•Check the fuse for continuity.
Refer to “CHECKING THE FUSES” in
Chapter 3.
2. Battery.
•Check the condition of the battery.
Refer to “CHECKING AND CHARGING
THE BATTERY” in Chapter 3.
Min. open-circuit voltage:
12.8 V or more at 20°C (68°F)
CONTINUITY
DISCONTINUTY
Replace the fuse.
INCORRECT
•Clean the battery terminals.
•Recharge or replace the battery.
Refer to “BATTERY INSPECTION” in
Chapter 3.
*
CORRECT
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TRBL
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CHAPTER 8°
TROUBLESHOOTING
FAILURE TO START/DIFFICULTIES IN STARTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
FUEL SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
ELECTRICAL SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2
POOR ENGINE COMPRESSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2
POOR PERFORMANCE AT IDLE SPEED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3
UNSATISFACTORY PERFORMANCE AT MEDIUM-HIGH SPEED . . . . . . . . . . . . . . . . . 8-3
DIFFICULTIES IN SHIFTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4
SHIFTING IMPOSSIBLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4
THE SHIFT PEDAL FAILS TO MOVE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4
DISENGAGING GEARS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4
CLUTCH SLIDES OR FAILS TO RELEASE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
CLUTCH SLIDES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
CLUTCH FAILS TO RELEASE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
DEFECTIVE BRAKES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-6
POOR BRAKING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-6
OIL LEAKS OR MALFUNCTIONING OF FRONT FORK . . . . . . . . . . . . . . . . . . . . . . . . . 8-6
OIL LEAKS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-6
MALFUNCTIONING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-6
UNSTABLE STEERING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-7
DEFECTIVE FUNCTIONING OF LIGHTS AND INDICATORS . . . . . . . . . . . . . . . . . . . . . 8-8
POOR HEADLIGHT ILLUMINATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-8
FREQUENT BURNING OF BULB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-8
DIRECTION INDICATORS FAIL TO TURN ON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-8
DIRECTION INDICATORS FAIL TO TURN OFF . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-8
DELAYED TURNING ON OF INDICATORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-9
EXCESSIVE INDICATOR INTERMITTENCE FREQUENCY . . . . . . . . . . . . . . . . . . . 8-9
THE HORN FAILS TO WORK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-9
OVERHEATING OF ENGINE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-9
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FAILURE TO START/
DIFFICULTIES IN STARTING
8-1
TRBL
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TROUBLESHOOTING
NOTE:
The troubleshooting tables that follow do not identify every cause of trouble. They may however prove
helpful as a guide to identifying trouble. To inspect, adjust or replace parts, refer to the appropriate sec-
tion in the manual.
FAILURE TO START/DIFFICULTIES IN STARTING
FUEL SYSTEM
Fuel tank
Fuel cock
Carburetor
Air filter PROBABLE CAUSES
•Empty
•Fuel filter obstructed
•Fuel tank air cap passage obstructed
•Petrol contains water or impurities or is adulterated
•Hose obstructed
•Fuel filter obstructed
•Petrol contains water or impurities or is adulterated
•Pilot jet obstructed
•Pilot air passage obstructed
•Infiltrations of air
•Deformation of float
•Needle valve worn or scratched
•Needle valve seat insufficiently sealed
•Fuel level set wrongly
•Pilot jet set wrongly
•Starter jet obstructed
•Malfunctioning of the starter piston
•Air filter element obstructed
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POOR PERFORMANCE AT IDLE SPEED/
UNSATISFACTORY PERFORMANCE AT MEDIUM-HIGH SPEED
8-3
TRBL
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Carburetor
Electrical system
Valves PROBABLE CAUSES•The starter piston fails to return freely
•Pilot jet obstructed or loose
•Pilot jet obstructed
•Pilot air screw wrongly set
•Idle speed wrongly set
(throttle valve stop screw)
•Throttle cable free play wrongly set
•Carburetor flooded
•Valve clearance wrongly set
Air filter
•Air filter element obstructed
POOR PERFORMANCE AT IDLE SPEED
See “FAILURE TO START/DIFFICULTIES IN STARTING”.
(FUEL SYSTEM, ELECTRICAL SYSTEM, COMPRESSION SYSTEM and Valve clearance)
Carburetor
PROBABLE CAUSES
•Petrol contains water or impurities or is adulterated
•Infiltrations of air
•Deformation of float
•Defective diaphragm
• Needle valve worn or scratched
•Needle valve seat insufficiently sealed
•Needle stop position incorrect
•Fuel level set wrongly
•Main jet obstructed or loose
•Main nozzle obstructed or loose
UNSATISFACTORY PERFORMANCE AT MEDIUM-HIGH SPEED
•Defective battery
•Defective spark plug
•Defective ignition unit
•Defective AC magneto
•Defective ignition coil
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DEFECTIVE FUNCTIONING OF LIGHTS AND INDICATORS/ OVERHEATING OF ENGINE
8-9
TRBL
SHTG
?
PROBABLE CAUSES
•Indicator lamp relay defective
•Insufficient battery capacity
(battery almost flat)
•Incorrect bulb
•Main switch or direction indicator switch defec-
tive
DELAYED TURNING ON OF INDICATORS
PROBABLE CAUSES
•Battery flat
•Main switch or horn switch defective
•Horn wrongly set
•Defective horn
•Harness cut off
THE HORN FAILS TO WORK
OVERHEATING OF ENGINE
PROBABLE CAUSES
•Incorrect bulb
•Indicator lamp relay defective
EXCESSIVE INDICATOR
INTERMITTENCE FREQUENCY
Ignition system
Fuel feed system PROBABLE CAUSES
•Incorrect electrode gap of spark plug
•Spark plug thermal gradation wrong
•Ignition unit defective
•Incorrect carburetor main jet (incorrect setting)
•Incorrect fuel level
•Air filter element obstructed
Engine compression
•Excess of carbon deposits
Engine oil
•Incorrect oil level
•Incorrect oil viscosity
•Incorrect oil gradation
Brake
•Pads fail to return freely (remains blocked)
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