TM 5-3895-383-24
6.
Engine used in a lug condition:
Lugging can occur when there is too much load
applied to the engine or the engine is run at a lower
rpm. This low rpm causes a reduction in air flow
through the radiator, and a reduction in the flow of
coolant through the system. This combination of
less air and less coolant flow during high input of
fuel will cause above normal heating.
Problem 29: Starter Motor Does Not Turn
Probable Cause(s):
Low Battery Voltage
Defective Cable Or Connection (Battery To Starter)
Defective Starter Solenoid
Defective Starter Motor
Inside Problem Prevents Crankshaft From Turning
1.
Low or no battery voltage:
Check battery voltage. If battery voltage is less
than 8 volts for a 12 volt system, or 16 volts for a 24
volt system, put a charge on the battery. If battery
will not hold a charge, load test the battery as
shown in the Electrical System of the Testing And
Adjusting Section of this Service Manual.
2.
Defective switch, defective wiring or connection in
switch circuit:
With ignition switch in the "START" position, check
voltage at switch connection on starter solenoid. If
there is no voltage, or if the voltage is low at this
connection and there is good voltage at the battery,
check for a detective cable or connection between
the battery and the starter.
3.
Defective starter solenoid:
Remove and repair a solenoid which does not work
when voltage is correct at both the battery and
ignition switch connections.
4.
Defective starter motor:
If the solenoid works and the starter motor does not
turn the crankshaft, the starter motor is defective.
Before removing the starter motor, turn the
crankshaft by hand to be sure a mechanical failure
inside the engine, transmission, or power take-off is
not preventing the crankshaft from turning. If the
crankshaft turns freely by hand, engage the starter
motor again. If the starter motor still will not work,
remove the starter motor. Repair or replace the
starter motor.
5.
Inside problem prevents crankshaft from turning:
If the crankshaft cannot be turned after disconnecting
the transmission and/or the power take-off, remove
the fuel nozzles and check for fluid in the cylinders
while turning the crankshaft. If fluid in the cylinders is
not the problem, the engine must be disassembled to
check for other internal problems. Some of the
possible problems are bearing seizure, piston seizure,
and valves making contact with the pistons.
Problem 30: Alternator Gives No Charge
Probable Cause(s):
Loose Drive Belt For Alternator
Charging Or Ground Return Circuit Or Battery
Connections Have A Defect
Brushes Have A Defect
Rotor (Field Coil) Has A Defect
1.
Loose drive belt for alternator:
Make an adjustment to put the correct tension on
the drive belt.
2.
Charging or ground return circuit or battery connections
have a defect:
Inspect all cables and connections. Clean and
tighten all connections. Make replacement of
defective parts.
3.
Brushes have a defect:
Install new brushes.
4.
Rotor (field coil) has a defect:
Install a new rotor.
Problem 31: Alternator Charge Rate Is Low Or Not
Regular
Probable Cause(s):
Loose Drive Belt For Alternator
Charging Or Ground Return Circuit Or Battery
Connections Have A Defect
Alternator Regulator Has A Defect
Alternator Brushes Have A Defect
Rectifier Diodes Have A Defect
Rotor (Field Coil) Has A Defect
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