Specific Gravity Test - Polaris msx 110 Service Manual

Specific Gravity Test

A tool such as the battery hydrometer can be used to measure electrolyte strength or specific gravity. As the
battery goes through the charge-discharge cycle, the electrolyte goes from a heavy (more acidic) state at full
charge to a light (more water) state when discharged. The hydrometer can measure state of charge and
differences between cells in a multi-cell battery. Readings of 1.270 or greater should be observed in a fully
charged battery. Differences of more than .025 between the lowest and highest cell readings indicate a need to
replace the battery.
Open Circuit Voltage
STATE OF CONVENTIONAL
CHARGE LEAD-ACID
100% Charged 12.60V
75% Charged 12.40V
50% Charged 12.10V
25% Charged 11.90V
0% Charged less than 11.80V
Specific Gravity
STATE OF CONVENTIONAL
CHARGE* LEAD-ACID
100% Charged 1.270
75% Charged 1.210
50% Charged 1.160
25% Charged 1.120
0% Charged less than 1.100
* At 80_F
NOTE: Subtract .01 from the specific gravity reading at 40_ F.
Battery Hydrometer
PN 2870836
Load Test
A battery may indicate a full charge condition in the OCV test and the specific gravity test, but still not have the
storage capacity necessary to properly function in the electrical system. For this reason a battery capacity or load
test should be conducted whenever poor battery performance is encountered.
NOTE: This test cannot be performed with an engine or starting system that is not working properly.
1. Attach a multitester to the battery. The reading should be 12.4 DCV or greater.
2. Engage electric starter and view registered battery voltage while cranking engine. Continue the test for 15
seconds. During this cranking period, the observed voltage should not drop below 9.5 volts. If the beginning
voltage is 12.4 or higher and the cranking voltage drops below 9.5 volts during the test, replace the battery.
8.6
ELECTRICAL SYSTEMS
YUMICRON
TYPE
12.70V
12.50V
12.20V
12.0V
less than 11.9V
YUMICRON
TYPE
1.275
1.225
1.175
1.135
less than 1.115
Detail A
2004 Four Stroke PWC Service Manual
1.10
1.15
1.20
1.25
1.30