Starter No-Load Test
- Turn carbon pile off and connect test equipment to starter. See Fig 1
. Close switch, adjust carbon pile to obtain 10 volts. Compare RPM and amperage readings with specifications. See the STARTER NO-LOAD TEST SPECIFICATIONS
table.CAUTION: DO NOT apply more voltage than specified. Excessive voltage may cause armature to throw windings due to excessive speed.
- If current draw and RPM meet specification, starter motor is okay. If test indicates low free speed and high current draw, unit may have tight, dirty or worn bearings, shorted or grounded armature, bent armature shaft, or grounded fields.
- Failure to operate with high current draw indicates direct ground in terminal fields or frozen bearings. Failure to operate with no current draw indicates an open field circuit, open solenoid windings, open armature coils or broken brush springs.
- Low RPM and low current draw indicates high internal resistance due to poor connections, defective leads or dirty commutator. High free speed and high current draw indicate shorted fields.