Checking The Spark Plug - Yamaha F2.5A Service Manual

CHK
ADJ
3. Slowly pull the starter rope to set the pis-
ton position to TDC of the compression
stroke.
NOTE:
• Make sure that the rocker arms 7 are not
pushing the intake valve 8 and exhaust
valve 9.
• Check the position of the piston from the
spark plug installation hole 0.
• Do not turn the flywheel magnet counter-
clockwise.
4. Check the valve clearance. Adjust if out
of specification.
NOTE:
• Check the valve clearance when the engine
is cold.
• Note the measurement.
Valve clearance:
Intake a:
0.08–0.12 mm
(0.0031–0.0047 in)
Exhaust b:
0.08–0.12 mm
(0.0031–0.0047 in)
3-5
Periodic checks and adjustments
5. Loosen the rocker arm locknuts A, and
then turn the rocker arm pivot B until the
specified valve clearance is obtained.
NOTE:
• To decrease the valve clearance, turn the
rocker arm pivot in direction c.
• To increase the valve clearance, turn the
rocker arm pivot in direction d.
6. Tighten the rocker arm locknuts to the
specified torque, and then check the
valve clearances. Adjust if necessary.
Rocker arm locknut A:
10 N·m (1.0 kgf·m, 7.4 ft·lb)
7. Install the cylinder head cover, fuel tank
bolts, spark plug, bottom cowling 2, fuel
cock lever, and carrying handle.

Checking the spark plug

1. Remove the grommet 1.
2. Disconnect the spark plug cap from the
spark plug, and then remove the spark
plug.
69M3E11