Yanmar 6LY3 series Service Manual page 44

PERIODIC MAINTENANCE
Checking the Electrolyte Level
• Check the level of fluid in the battery
(Figure 4-8, (2)). When the amount of fluid nears
the lower limit (Figure 4-8, (1)), fill with battery
fluid (commercially available) to the upper limit
(Figure 4-8, (3)). If operation continues with
insufficient battery fluid, the battery life is
shortened and the battery may overheat and
explode.
• Battery fluid tends to evaporate more quickly in
the summer, and the fluid level should be
checked more often.
• If the engine cranking speed is so slow that the
engine does not start, recharge the battery.
• If the engine still will not start after charging,
replace the battery.
• When parking, remove the battery and store in a
warm place if the vessel will be left in ambient
temperatures below -15°C (5°F).
Figure 4-8
(4)
(3)
Figure 4-8
1 – Lower Limit
2 – Electrolyte Level
3 – Upper Limit
4 – Grease
Testing Battery Charge
• Use a battery tester (Figure 4-9, (1)) or
hydrometer to check battery condition. If the
battery is discharged, recharge it.
4-12
(1)
(2)
0006165
© 2007 Yanmar Marine International
Periodic Maintenance Procedures
• Measuring Battery Charge With Battery Tester
Figure 4-9
Figure 4-9
1 – Battery Tester
Measurement with a Battery Tester
When checking the battery with the battery tester,
connect the red clip of the tester to the positive (+)
battery terminal and black clip to the negative (-)
battery terminal. Read the battery charge indicator.
Green zone: Normal
Yellow zone: Slightly discharged
Red zone: Defective or completely discharged
Measuring Battery Charge with a Hydrometer
When using a hydrometer, the measured specific
gravity must be corrected according to the
temperature at the time of measurement. The
specific gravity of battery electrolyte is defined
using 20°C (68°F) as the standard. Since the
specific gravity increases or decreases by 0.0007
when the temperature varies by 1°C (1°F), correct
the value according to the equation below.
S = St + 0.007 ( t - 20 )
20
Specific gravity at measurement
Converted specific gravity at 20 C
6LY3 Service Manual
(1)
0006166
Electrolyte temperature
at measurement
001348-01E