Toro Workman MDX-D, Service Manual

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Workman MDX--D Electrical System Page 5 -- 25
Battery Testing
1. If battery caps can be removed, conduct a hydrome-
ter 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
10
o
F (6
o
C) above 80
o
F (27
o
C) add 0.004 to the spe-
cific gravity reading. For each 10
o
F (6
o
C) below 80
o
F
(27
o
C) subtract 0.004 from the specific gravity read-
ing.
Example: Cell Temperature 100 o F
Cell Gravity 1.245
ADD (20 o above 80 o F) 0.008
Correction to 80 o F 1.253
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 Battery Charging or until the specific gravity of
all cells is 1.225 or greater with the difference in spe-
cific gravity between the highest and lowest cell less
than 0.050. If these charging conditions can not 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 battery load tester manufacturer’s
instructions when using a load tester.
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 before load testing.
B. Make sure the battery terminals are free of corro-
sion.
C. If the battery has been charged, apply a 270 amp
load for fifteen (15) seconds to remove the surface
charge. Use a battery load tester following the
manufacturer’s instructions.
D. Measure the temperature of the electrolyte in the
center cell.
E. Connect a battery load tester to the battery termi-
nals following the manufacturer’s instructions .
Connect a digital multimeter to the battery terminals.
F. Apply a test load of 270 amps (one half the battery
CCA performance) for fifteen (15) seconds.
G. Take a battery voltage reading after fifteen (15)
seconds, then remove the load. Record this test volt-
age reading.
H. Using the table below, determine the minimum
test voltage for the cell temperature reading.
Minimum
Test Voltage
Battery Electrolyte
Temperature
9.6 70
o
F (and up) 21
o
C (and up)
9.5 60
o
F 16
o
C
9.4 50
o
F 10
o
C
9.3 40
o
F 4
o
C
9.1 30
o
F --1
o
C
8.9 20
o
F --7
o
C
8.7 10
o
F --12
o
C
8.5 0
o
F --18
o
C
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.
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