Spark Plugs; General - Yamaha F20A Service Manual

INSP
ADJ

GENERAL

NOTE:
Batteries vary
Consult your
instructions.
First, disconnect the negative lead, then
the positive lead.
1. Check:
Battery fluid level
Below the minimum level mark →
Add distilled water to the proper
level.
Battery fluid specific gravity
Less than 1.280 → Recharge the bat-
tery.
Battery fluid specific gravity:
1.280 at 20 ˚C (68 ˚F)

Spark plugs

1. Inspect:
Electrodes 1
Cracks/excessive wear→ Replace.
Insulator color 2
Distinctly different color →
Check the engine condition.
Color guide:
Medium to light tan color:
Normal
Whitish color:
Lean fuel mixture
Plugged jet(s)
Air leak
Wrong setting
Blackish color:
Rich mixture
Defective ignition system
Excessive idling
Wrong spark plug
2. Clean:
Spark plugs
(with a spark plug cleaner or wire
brush)
3-10
among manufacturers.
battery manufacturer's
E