Yamaha F50 Service Manual

							62Y3A118-10
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Wiring harness8
Connect to:
1Tiller handle main 
switch or remote 
control box or wiring 
harness extension
2Power trim and tilt 
relay
3Ground
4Starter relay
5Positive battery lead
6Prime Start7Warning indicator or 
digital tachometer
8CDI unit
9Power trim and tilt 
switch or trailer switch
0Rectifier Regulator
AThermoswitch
BIgnition coil
COil pressure switchÈPower trim and tilt 
model
B: Black
Br : Brown
G: Green
L: Blue
Lg : Light green
P: Pink
R: Red
Sb : Sky blueW: White
B/O : Black/orange
B/W : Black/white
P/B : Pink/black
P/W : Pink/white
Y/B : Yellow/black
Y/R : Yellow/red
Electrical components / Wiring harness 
						

							ELECElectrical systems
–+
8-1162Y3A11
Ignition system and Ignition control system8
1Spark plug
2Ignition coil
3Charge coil
4Pulser coil
5Engine start switch
6Engine shut-off switch
710-pin coupler
8CDI unitB: Black
Br : Brown
L: Blue
W: White
B/O : Black/orange
B/W : Black/white
W/B : White/black
W/R : White/red 
						

							62Y3A118-12
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1Thermoswitch
2Oil pressure switch
3CDI unit
4Digital tachometer
5Oil pressure warning 
indicator
6Overheat warning 
indicator
7Remote control box
8Warning indicatorÈRemote control model
ÉTiller handle modelB: Black
G: Green
R: Red
Y : Yellow
Gy/B : Green/black
P/B : Pink/black
P/W : Pink/white
Y/B : Yellow/black
Y/R : Yellow/red
Ignition system and Ignition control system 
						

							ELECElectrical systems
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8-1362Y3A11
Checking the ignition spark gap
1. Disconnect the spark plug caps from the
spark plugs.
2. Connect a spark plug cap to the special
service tool.
ÈFor USA and Canada
ÉFor worldwide
3. Set the spark gap length on the adjusting
knob.
ÈFor USA and Canada
ÉFor worldwide
4. Crank the engine and observe the spark
through the discharge window of the
spark gap tester. Check the ignition coil if
out of specification.
ÈFor USA and Canada
ÉFor worldwide
 WARNING
•Do not touch any of the connections of
the spark gap tester leads.
•Do not let sparks leak out of the
removed spark plug caps.
•Keep flammable gas or liquids away,
since this test can produce sparks. Dynamic spark tester: YM-34487
Ignition tester: 90890-06754
Ignition spark gap: 9 mm (0.35 in) 
						

							62Y3A118-14
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Checking the spark plug caps
1. Remove the spark plug caps from the
high-tension cords by turning the caps
counterclockwise.
2. Measure the spark plug cap resistance.
Replace if out of specification.
Checking the ignition coil
1. Remove the spark plug caps from the
high-tension cords by turning the caps
counterclockwise.
2. Measure the ignition coil resistance.
Replace if out of specification. Spark plug cap resistance: 3.75–6.25 kΩ
 
Ignition coil resistance:
Primary coil:
Orange (O) – Black (B)
0.08–0.11 Ω
 at 20 °C (68 °F)
Secondary coil:
High-tension cord – High-tension cord
3.5–4.7 kΩ
 at 20 °C (68 °F)
Ignition system and Ignition control system 
						

							ELECElectrical systems
–+
8-1562Y3A11
Checking the CDI unit
1. Measure the CDI unit output peak volt-
age. If below specification, measure the
charge coil output peak voltage and the
pulser coil output peak voltage. Replace
the CDI unit if the output peak voltage of
both coils is above specification.
 WARNING
When checking the peak voltage do not
touch any of the connections of the digital
tester leads.
NOTE:
Use the peak voltage adaptor with the digi-
tal circuit tester.
When measuring the peak voltage, set the
selector on the digital circuit tester to the
DC voltage mode.
Checking the charge coil
1. Measure the charge coil output peak volt-
age. Replace the stator coil if below
specification.
 WARNING
When checking the peak voltage do not
touch any of the connections of the digital
tester leads.
NOTE:
Use the peak voltage adaptor with the digi-
tal circuit tester.
When measuring the peak voltage, set the
selector on the digital circuit tester to the
DC voltage mode. Digital multimeter: YU-34899-A
Digital circuit tester: 90890-03174
Peak voltage adaptor:
YU-39991 / 90890-03172
CDI unit output peak voltage:
Black/orange (B/O) – Black (B)
Black/white (B/W) – Black (B)
r/min
UnloadedLoaded
Cranking 1,500 3,500
DC V 126 150 151 116 
						

							62Y3A118-16
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Checking the pulser coil
1. Measure the pulser coil output peak volt-
age. Replace the pulser coil if below
specification.
 WARNING
When checking the peak voltage do not
touch any of the connections of the digital
tester leads.
NOTE:
Use the peak voltage adaptor with the digi-
tal circuit tester.
When measuring the peak voltage, set the
selector on the digital circuit tester to the
DC voltage mode
.
Checking the pulser coil air gap
1. Turn the flywheel clockwise to align the
projection of the flywheel with the pulser
coil projection.
2. Measure the gap between both projec-
tions with a thickness gauge 1
. Adjust if
out of specification. Digital multimeter: YU-34899-A
Digital circuit tester: 90890-03174
Peak voltage adaptor:
YU-39991 / 90890-03172
Test harness (2 pins):
YB-06767 / 90890-06767
Charge coil output peak voltage:
Brown (Br) – Blue (L)
r/min
UnloadedLoaded
Cranking 1,500 3,500
DC V 144 137 169 129
Charge coil resistance (use as reference):
Brown (Br) – Blue (L)
272–408 Ω
 at 20 °C (68 °F)
Digital multimeter: YU-34899-A
Digital circuit tester: 90890-03174
Peak voltage adaptor:
YU-39991 / 90890-03172
Test harness (2 pins):
YB-06767 / 90890-06767
Pulser coil output peak voltage:
White/red (W/R) – White/black (W/B)
r/min
UnloadedLoaded
Cranking 1,500 3,500
DC V 6.3 3.5 7.4 11.2
Pulser coil resistance (use as reference):
White/red (W/R) – White/black (W/B)
396–594 Ω
 at 20 °C (68 °F)
Pulser coil air gap:
0.5–1.0 mm (0.020–0.039 in)
Ignition system and Ignition control system 
						

							ELECElectrical systems
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8-1762Y3A11
3. Remove the flywheel magnet nut and fly-
wheel magnet.
4. Loosen the pulser coil screws, adjust the
pulser coil 2
 position, and then tighten
the screws finger tight.
5. Set the flywheel magnet and then check
the gap again and, if necessary, repeat
steps 3–5.
6. Tighten the pulser coil screws and fly-
wheel magnet nut to the specified
torques.
Checking the engine start switch
1. Check the engine start switch for continu-
ity. Replace if there is no continuity.
Checking the engine shut-off switch
1. Check the engine shut-off switch for con-
tinuity. Replace if there is no continuity.
Pulser coil screw:
4 N·m (0.4 kgf·m, 2.9 ft·lb)
Flywheel magnet nut:
160 N·m (16 kgf·m, 116 ft·lb)
Lead color
Switch 
positionWhite 
(W)Black 
(B)Red 
(R)Pink 
(P)
Brown 
(Br)
OFF
ON
START
Lead color
White (W)
Black (B)
Remove the lock 
plate a
 
Install the lock 
plate b
 
Push the button c
  
						

							62Y3A118-18
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Checking the thermoswitch
1. Place the thermoswitch in a container of
water and slowly heat the water.
2. Check the switch for continuity at the
specified temperatures. Replace if out of
specification.
aTemperature
bTime
cNo continuity
dContinuity
Checking the oil pressure switch
1. Connect the special service tool to the oil
pressure switch.
2. Slowly operate the special service tool.3. Check the switch for continuity at the
specified pressure. Replace if there is no
continuity.
Thermoswitch continuity temperature:
Pink (P) – Black (B)
e
: 76–84 °C (164–183 °F)
f
: 63–77 °C (145–170 °F)
Pressure/vacuum tester: YB-35956-A
Vacuum/pressure pump gauge set:
90890-06756
Specified oil pressure:
50 kPa (0.5 kgf/cm
2, 7.11 psi)
Ignition system and Ignition control system 
						

							ELECElectrical systems
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8-1962Y3A11
Starting system8
1Fuse
210-pin coupler
3Engine start switch
4Starter motor
5Battery
6Neutral switch
7Starter relay
ÈTiller handle modelB: Black
Br : Brown
R: Red