Toro Groundsmaster 360 Service Manual page 233

Battery Testing
1. Conduct a hydrometer test of the battery electrolyte.
IMPORTANT: Make sure the area around the cells is
clean before opening the battery caps.
A. Measure the specific gravity of each cell with a
hydrometer. Draw electrolyte in and out of the
hydrometer barrel prior to taking a reading to warm--
up the hydrometer. At the same time, take the tem-
perature of the cell.
B. Temperature correct each cell reading. For each
o o
10 F (5.5 C) above 80
specific gravity reading. For each 10
o o
low 80 F (27 C) subtract 0.004 from the specific
gravity reading.
Example: Cell Temperature
Cell Gravity
o o
100 F minus 80 F equals 20
o o
(38 C minus 27 C equals 11
o
20 F multiply by 0.004/10
o
(11 C multiply by 0.004/5.5
ADD (conversion above)
o
Correction to 80 F (27
C. If the difference between the highest and lowest
cell specific gravity is 0.050 or greater or the lowest
cell specific gravity is less than 1.225, charge the bat-
tery. Charge at the recommended rate and time giv-
en in Charging or until all cells specific gravity is
1.225 or greater with the difference in specific gravity
between the highest and lowest cell less than 0.050.
If these charging conditions cannot be met, replace
the battery.
2. Perform a high--discharge test with an adjustable
load tester.
This is one of the most reliable means of testing a battery
as it simulates the cold--cranking test. A commercial bat-
tery load tester is required to perform this test.
CAUTION
Follow the manufacturer's instructions when us-
ing a battery load tester.
A. Check the voltage across the battery terminals
prior to testing the battery. If the voltage is less than
12.4 VDC, charge the battery before proceeding with
test.
Groundsmaster 360
o o
F (27 C) add 0.004 to the
o o
F (5.5 C) be-
o
100 F
1.245
o
F
o
C)
o
F equals 0.008
o
C equals 0.008)
0.008
o
C) 1.253
Page 5 - - 59
B. Make sure battery terminals are free of corrosion.
C. Measure the electrolyte temperature of the cen-
ter battery cell.
D. Connect a battery load tester to the battery termi-
nals following the manufacturer's instructions.
Connect a digital multimeter to the battery terminals.
E. If the battery has recently been charged, apply a
150 amp load for fifteen (15) seconds to remove the
surface charge. Wait ten (10) minutes before pro-
ceeding with load test.
F. Apply a test load of 270 amps (one half of the bat-
tery cranking performance rating) for fifteen (15) se-
conds.
G. After test load has been applied for fifteen (15) se-
conds, take the test voltage reading and then re-
move the load. Record test voltage reading.
H. Using the table below, determine the minimum
voltage based on the center cell electrolyte tempera-
ture reading.
Minimum Battery Electrolyte
Voltage
o
9.6 70 F (and up)
o
9.5 60 F
o
9.4 50 F
o
9.3 40 F
o
9.1 30 F
o
8.9 20 F
o
8.7 10 F
o
8.5 0 F
I. If the test voltage is below the minimum, replace
the battery. If the test voltage is at or above the mini-
mum, return the battery to service.
3. After connections are made, apply battery terminal
protector (Toro Part No. 107--0392) or a light coat of
grease on all battery posts and cable connectors to re-
duce corrosion.
Temperature
o
21 C (and up)
o
16 C
o
10 C
o
4 C
o
--1 C
o
--7 C
o
--12 C
o
--18 C
Electrical System