Lower Unit/General; Anode; Spark Plug - Yamaha F4 Service Manual

INSP
ADJ
2

LOWER UNIT/GENERAL

1
2
1
8 Apply the specified pressure.
Pressure:
100 kPa (1.0 kg/cm
8 Check that the lower unit holes the
specified pressure for ten seconds.
NOTE:
Do not over-pressurerize the lower unit.
Excessive pressure may cause the air to
leak out.
GENERAL

Anode

1. Inspect:
Anode 1 (engine)
9
Anode 2 (lower unit)
9
Scales ® Clean.
Oil/Grease ® Clean.
Wear (1/2)/Damage ® Replace.
cC
Can not oil, grease or paint the anode, or it
will not operate properly.

Spark plug

1. Remove:
9 Spark plug
2. Inspect:
Electrodes 1
9
Cracks/excessive wear ® Replace.
Insulator color 2
9
Distinctly different color ® Check the
engine condition.
Color guide:
Medium to light tan color:
Normal
Whitish color:
8 Lean fuel mixture
8 Clogged jet(s)
8 Wrong setting
Blackish color:
8 Rich mixture
8 Defective ignition system
8 Excessive idling
8 Wrong spark plug
3-11
E
2 , 14.2 psi)