Toro Groundsmaster 3500 30807 Service Manual page 227

Battery Inspection and Maintenance
1. Replace battery if case is cracked or leaking.
2. Check battery terminal posts for corrosion. Use wire
brush to clean corrosion from posts.
IMPORTANT: Before cleaning the battery, tape or
block vent holes to the filler caps and make sure the
caps are on tightly.
3. Check for signs of wetness or leakage on the top of
the battery which might indicate a loose or missing filler
cap, overcharging, loose terminal post or overfilling.
Also, check battery case for dirt and oil. Clean the bat-
tery with a solution of baking soda and water, then rinse
it with clean water.
4. Check that the cover seal is not broken away. Re-
place the battery if the seal is broken or leaking.
5. Check the electrolyte level in each cell, if possible. If
the level is below the tops of the plates in any cell, fill all
cells with distilled water between the minimum and max-
imum fill lines. Charge at 15 to 25 amps for fifteen (15)
minutes to allow sufficient mixing of the electrolyte.
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
10F (5.5C) above 80F (27C) add 0.004 to the specif-
ic gravity reading. For each 10F (5.5C) below 80F
(27C) subtract 0.004 from the specific gravity read-
ing.
Example: Cell Temperature
Cell Gravity
100F minus 80F equals 2F
(38C minus 27C equals 11C)
20F multiply by 0.004/10F equals 0.008
(11C multiply by 0.004/5.5C equals 0.008)
ADD (conversion above)
Correction to 80F (26.7C)
Groundsmaster 3500
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 (in this section) or until the
specific gravity for all cells is 1.225 or greater with the
difference in specific gravity between the highest and
lowest cell less than 0.050. If these charging condi-
tions 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.
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
12.4 VDC, recharge the battery.
B. If the battery has been charged, apply a 150 amp
load for fifteen (15) seconds to remove the surface
charge. Use a battery load tester following the
manufacturer's instructions.
C. Make sure battery terminals are free of corrosion.
D. Measure the temperature of the center battery
cell.
E. Connect a battery load tester to the battery ter-
minals following the load tester manufacturer's in-
structions. Connect a digital multimeter to the battery
terminals.
F. Apply a test load of 325 amps (one half the Crank-
ing Performance rating of the battery) for fifteen (15)
seconds.
100F
1.245
G. Take a battery voltage reading after the load has
been applied to the battery for fifteen (15) seconds,
then remove the load. Record the voltage reading.
H. Using the table below, determine the minimum
0.008
voltage for the cell temperature reading:
1.253
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CAUTION
Electrical System