Yamaha F40BED, Service Manual

Page: 456 / 537

IGNITION SYSTEM
8-13
E
– +
ELEC
CHECKING THE SPARK PLUG CAPS
1. Check:
• Spark plug cap
Loose connection
→
Tighten.
Cracks/damage
→
Replace.
Replacement steps
(1) To remove the spark plug cap turn it
counterclockwise.
(2) To install the spark plug cap turn it
clockwise until it is tight.
2. Measure:
• Spark plug cap resistance
Out of specification
→
Replace.
CHECKING THE IGNITION COIL
Measure:
• Ignition coil resistance
Primary
Out of specification
→
Replace.
Secondary
Out of specification
→
Replace.
Spark plug cap resistance
4.0 - 6.0 k
Ω
Ω Ω
Ω
B/W
O
B/W
(Primary)
(Secondary)
Ignition coil resistance
Primary
O-B/W
Secondary
B/W
0.17 - 0.25
Ω Ω Ω Ω
2.7 - 3.7 k
Ω Ω Ω Ω