TOHATSU 40 Service Manual page 200

10. As soon as the charging process has completed, measure the
battery voltage and specific gravity. The voltage should be 15 to 16
volts and the specific gravity should be 1.260 (corrected for
temperature). If either of these conditions are not met, replace the
battery.
Terminal Voltage Test
Batteries produce an explosive mixture of oxygen
and hydrogen! Keep any sparks or open flame
away from battery while charging or performing
terminal voltage test. When you charge the
battery, remove the filler caps (if any) from each
cell.
To avoid the potential for an explosion with fuel
vapor, always remove the battery from boat when
you are charging it.
Always remove the negative cable first, then the
positive one.
Check electrolyte level and specific gravity before
running the terminal voltage test.
1. Connect the Variable Load High Rate Discharge Tester to battery
terminals.
2. Discharge at 210 amperes (3 x ampere hour rating of battery) for
15 seconds.
3. Measure voltage at battery terminals. If 9.6 volts, or higher,
battery has a good output capacity. If lower than 9.6 volts, replace
the battery.
Charging
See the Charging Capacity Test procedure in this section for the
correct battery charging procedure.
3-/ 4-Cylinder
WARNING
WARNING
WARNING
ELECTRICAL SYSTEM
7-21