Toro Groundsmaster 580-D Service Manual page 310

2. 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_F (26.7
the specific gravity reading. For each 10
o o
below 80 F (26.7 C) subtract 0.004 from the spe-
cific gravity reading.
Example: Cell Temperature 100
Cell Gravity
ADD (20
Correction to 80
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
battery. Charge at the recommended rate and time
given in Charging or until all cells specific gravity is
1.225 or greater with the difference in specific grav-
ity between the highest and lowest cell less than
0.050. If these charging conditions can not be met,
replace the battery.
3. 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
using a battery tester.
Electrical System (S/N 30101 & Up) (Rev. E)
o
C) add 0.004 to
o
F (5.5
o
F
1.245
o o
above 80 F) 0.008
o
F 1.253
A. Check the voltage across the battery terminals
prior to testing the battery. If the voltage is less than
12.0 VDC, recharge the battery.
B. If the battery has been charged, apply a 150 amp
load for 15 seconds to remove the surface charge.
Use a battery load tester following the manufactur-
er's instructions.
C. Make sure the battery terminals are free of corro-
sion.
D. Measure the temperature of the center cell.
o
C)
E. Connect a battery load tester to the battery ter-
minals following the manufacturer's instruc-
tions. Connect a digital multimeter to the battery
terminals.
F. Apply a test load of one half the Cranking Perfor-
mance rating (see Fig. 17) of the battery for 15 se-
conds.
G. Take a voltage reading at 15 seconds, then re-
move the load.
H. Using the table below, determine the minimum
voltage for the cell temperature reading.
Minimum
Voltage
9.6
9.5
9.4
9.3
9.1
8.9
8.7
8.5
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.
Page 8 - - 16
Battery Electrolyte
Temperature
o o
70 F (and up) 21.1
o
60 F 15.6
o
50 F 10.0
o
40 F
o
30 F --1.1
o
20 F --6.7
o
10 F --12.2
o
0 F --17.8
Groundsmaster 580--D
C (and up)
o
C
o
C
o
4.4 C
o
C
o
C
o
C
o
C