Section C - Electrics
Service Procedures
Starting Circuit Test
C - 13 C - 13
9803-9450-1
Starting Circuit Test
Before carrying out the voltmeter tests, check that the
battery is in good condition and fully charged. Ensure that
all connections are clean and tight. Check that the 60 amp
primary fuse X is intact.
To prevent the engine starting during the tests ensure that
the engine shut off solenoid lead is disconnected at the fuel
pump.
Check the readings in the following sequence using a
voltmeter. Unless otherwise stated, the readings must be
taken with the starter switch in the 'start' position.
1 Connect the voltmeter across the battery terminals.
The reading in 'start' position should be 10.0 V
approximately.
A low reading probably indicates a fault in the starter
motor.
2 Connect the voltmeter between the starter main
terminal A and the commutator end bracket B. In the
'Start' position, the reading should not be more than
0.5 V below the reading obtained in Test 1.
3 Connect the voltmeter between the solenoid terminal
C and a good earth. Minimum reading in 'start'
position: 8.0 V.
If the reading is less than specified, connect the
voltmeter between the neutral start relay terminal D
and earth. An increase in reading to 8.0 V indicates a
fault in the wiring from the start relay to the solenoid.
If the reading between terminal D and earth is below
8.0 V, connect the voltmeter between terminal E and
earth. An increase in the reading to 8.0 V indicates
either a faulty start relay or a relay solenoid. Check
also the solenoid earth connection.
If the reading between E and earth is less than 8.0 V,
the fault must be in either the starter switch (terminals
F and G) or in the wiring between the solenoid, starter
switch, and the start relay.
4 Connect the voltmeter between the battery negative
and starter earth connection B. The reading in the
'start' position should be practically zero.
If the reading is appreciably above zero, a high
resistance in the earth lead or connections is
indicated.
5 Connect the voltmeter between battery positive and
the starter main terminal A. With the starter switch
'off', the voltmeter should indicate battery voltage, but
it should fall to practically zero when the switch is
turned to the 'on' position.
If the reading is appreciably above zero, a high
resistance is present in the insulated lead or in the
solenoid. Connect the voltmeter between the battery
positive and solenoid connection H. If the voltmeter
now reads zero with the switch closed, the fault is in
the solenoid.
Finally reconnect the engine shut off solenoid lead.
Fig 11.
A
B
C
ED GF X
H
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