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Alternator Output Test

  1. Disconnect multi-socket connector and remove molded cover from rear of alternator. (Cover may be pierced with a probe on some models in order to ground the field winding brush and by-pass the regulator.) Provide a test circuit as illustrated.
  2. Start engine and run to give 1, 500 alternator RPM (approximately 650-800 engine RPM). Test circuit bulb should be out.
  3. Increase engine speed to 2500-3, 000 RPM to give 6, 000 alternator RPM. Adjust variable resistor so voltmeter reads 14 volts and note ammeter reading equal to the nominal output rating for the appropriate alternator. If readings are not correct, alternator requires overhaul or replacement.
    NOTE: Do not connect variable resistor across battery for longer than is necessary to complete the test.
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