Yamaha F40BMHD, Service Manual

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CHK
ADJ
3-22
GENERAL
E
NOTE:
• Batteries vary among manufacturers.
Therefore, the following procedures
may not always apply. Consult your
battery manufacturer’s instructions.
• First, disconnect the negative lead, then
the positive lead.
Check:
• Electrolyte level
Below the minimum level mark
→
Add distilled water to the proper
level.
• Electrolyte specific gravity
Less than specification
→
Recharge
the battery.
CHECKING THE SPARK PLUGS
1. Check:
• Electrodes
Cracks/excessive wear
→
Replace.
• Insulator color
Distinctly different color
→
Check
the engine condition.
2. Clean:
• Spark plug
(with a spark plug cleaner or wire
brush.)
Electrolyte specific gravity
1.28 at 20°C (68°F)
2
1
Color guide
Medium to light tan color
Normal
Whitish color
•Lean fuel mixture
•Plugged jet(-s)
•Air leak
•Wrong setting
Blackish color
•Rich mixture
•Excessive oil usage
•Defective ignition system
•Defective spark plug
1
2