Manitowoc 999, Service And Maintenance Manual

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Reference
Only
POWER TRAIN 999 SERVICE/MAINTENANCE MANUAL
7-4
Published 05-16-17, Control # 233-03
Maintenance
Checking Battery State-of-Charge
Special equipment is required to properly determine the
condition of a battery that has been in service. However, a
voltmeter can be used to determine a battery’s state-of-
charge by checking the voltage between the battery
terminals (
Figure 7-3 ) ( Table 7-2 ).
This open-circuit test is the simplest test but not as accurate
in determining a battery’s condition as a hydrometer test.
The advantage is that the cell covers do not need to be
opened, eliminating the possibility of cell contamination and
electrolyte spill.
NOTE Do not use this test method if the battery has been
recently charged by a charger or alternator. Recent
charging places a high surface charge voltage
which is not a true indication of actual battery
voltage.
Table 7-2. Open Circuit Voltage
Consult the manual provided with the test meter for detailed
test information.
Troubleshooting—Slow Cranking
If the starter cranks too slowly and the battery is charged and
in good condition, do a voltage-drop test to make sure the
starter connections are good.
When cranking, a voltage drop of more than 0.2 volts
between the starting motor cable and ground can cause hard
starting regardless of a battery’s condition. The voltage drop
can be caused by a poor contact between the cable terminal
and ground or between the clamp terminal and the battery
post. Poor start-switch contacts and frayed, broken, or
corroded cables can also be the cause.
Quarterly Battery Maintenance
• Thoroughly clean the batteries and the holder with a
baking soda/water solution.
• If provided, make sure the drain holes are open in the
holder. If water collects in the holder, drill drain holes.
• Clean the posts and terminals. Lightly coat the posts
with petroleum jelly to prevent corrosion.
• Replace frayed, broken, or corroded cables.
• Replace the batteries if their containers are cracked or
worn to the point they leak.
• Ensure a good tight contact between the clamp
terminals and battery posts.
• Make sure the hold-downs are tight enough to prevent
battery movement but not so tight to cause distortion.
WARNING
Personal Injury Hazard!
Each battery weighs 59 lb (27 kg). Use proper lifting
procedures.
Item Description
1 Test Leads on Battery Terminals
2 Voltmeter
FIGURE 7-3
1 1 2
State-of-Charge Specific Gravity
Approximate
Open-Circuit
Voltage
(24V System)
100% 1.260 25.2
75% 1.230 24.8
50% 1.200 24.4
25% 1.170 24.0
0% 1.110 23.6