Yamaha YFM7FGPW Service Manual page 417

EBS01032
3. Spark plug
• Check the condition of the spark plug.
• Check the spark plug type.
• Measure the spark plug gap.
Refer to "CHECKING THE SPARK PLUG"
in chapter 3.
Standard spark plug
CR8E (NGK)
Spark plug gap
0.7 ~ 0.8 mm (0.028 ~ 0.031 in)
• Is the spark plug in good condition, is it of
the correct type, and is its gap within spec-
ification?
YES
NO
Re-gap or replace
the spark plug.
9 - 12
IGNITION SYSTEM
EBS01034
4. Ignition spark gap
• Disconnect the spark plug cap from the
spark plug.
• Connect the ignition checker 1 as shown.
2 Spark plug cap
• Set the main switch to "ON".
• Measure the ignition spark gap a.
• Crank the engine by pushing the start
switch and gradually increase the spark
gap until a misfire occurs.
Minimum ignition spark gap
6.0 mm (0.24 in)
• Is there a spark and is the spark gap within
specification?
NO
– +
ELEC
YES
The ignition system
is OK.