Hudson 1948 - 1952, Service Manual

Page: 142 / 333

6 - 6 ELECTRICAL SYSTEM
3. If a starter battery tester is used, turn the selector knob to
the 15 volt position.
4. With ignition key off, engage the starter motor and note
reading on the voltmeter. The cranking voltage should
read 5 volts or more.
CAUTION: Crank engine intermittently (not more than
30 seconds) to prevent starter motor from overheating.
5. If the voltmeter reading is less than 5 -Volts, check the
battery cables, ground straps and starter solenoid to
determine the cause for the low reading. See "Engine
Tune-Up", Section 2, Page 6.
FIGURE 4
AMPERAGE DRAW TEST:
1. Turn battery starter tester knob to "off" position.
2. Turn the voltmeter "selector switch" to the 15 volt
position and connect test leads, Figure 4.
3. Press starter switch and crank engine for approximately
15 seconds and note the "exact" reading on voltmeter.
4. Release starting motor switch and turn battery tester
control knob clockwise until volt meter reads "exactly"
the same as when cranking the engine with starter.
5. Read "Test Ammeter" for starting motor amperage draw.
6. After completing amperage draw test, turn control knob
to "off" position
7. Readings acquired by the above checks indicate the
amount of current required to crank the engine.
The reading should be 140 to 160 amperes at 120 RPM,
(Engine warm).
Excessively high readings will indicate a short in the
starting motor circuit or an excessive drag on the motor due
to a bent armature shaft or the field coils touching the
armature.
Low readings indicate excessive resistance in the circuit
caused by loose connection s, w o r n brushes, or weak brush
spring tension.
STARTER SOLENOID TEST:
1. Connect negative lead to "BAT" terminal of starter
solenoid switch and positive lead to the starting motor
terminal of starter solenoid switch, Figure 5.
FIGURE 5
2. Close the solenoid electrically to crank the engine; if the
reading is more than 0.2 volts, replace the solenoid switch.