G 1500 1/2 Ton Van V8-5.7L VIN R (1997)
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Seized bearings. This should have been noted by turning the armature by hand.
4. Failure to operate with no current draw indicates:
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Open field circuit. This can be checked after disassembly by inspecting internal connections and tracing the circuit with a test lamp.
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Open armature coils. Inspect the commutator for badly burned bars after disassembly.
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Broken brush springs, worn brushes.
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High insulation between the commutator bars or other causes which would prevent good contact between the brushes and commutator.
5. Low no-load speed and low current draw indicates a higher internal resistance due to poor connections, defective leads, dirty commutator and
causes listed under Step 4.
6. High free speed and high current draw indicates shorted fields. If shorted fields are suspected, replace the field coil assembly and check for
improved performance.
Starter Draw Test - 28-MT Starter Motor
TOOLS REQUIRED:
J 39200 Digital Multimeter
J 35590 Current Clamp
Important: Verify that both batteries are in good condition.
NOTICE: Never operate the starter motor more than 15 seconds at a time without pausing to allow it to cool for at least 2 minutes. Overheating will
damage the starter motor.
1. Disable the fuel system by removing the fuel solenoid fuse.
2. Calculate the current draw, and select the 200 A or 2000 A scale on the current clamp.
Starter Draw Test
3. Zero the current clamp, and clamp the tool to the negative battery cable.
4. Crank the engine and observe the meter readings. The reading should be 330 to 360 amps. If the amperage is over 360 amps, an internal starter
failure may be the cause. If the amperage is under 330 amps, a battery cable or connection may be the cause.
Starter Motor Test - SD-255 Starter Motor
Before disassembling the starter motor for repair perform the No-Load Test. See: No-Load Test - SD-255 Starter Motor
NOTICE: Never operate the starter motor more than 15 seconds at a time without pausing to allow it to cool for least two minutes. Overheating, caused
by too much cranking, will damage the starter motor.
