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For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 1996 🢒 GMC G Van 🢒 Engine 🢒 Engine Electrical 🢒 Generator Assembly Bench Check

Generator Assembly Bench Check CS-144

Tools Required

J 39200 Digital Multimeter

    Important: Perform the following inspection in order to verify operation of a repaired CS-144 generator:

  1. Mount the generator in a test stand. Ensure that the test stand is capable of driving a generator at 6500 RPM.

    2. Object Number: 1049 Size: SH
  2. Make the connections as shown.

    3. Important: Ensure that the batter is fully charged when making this test.

    Run the engine at 2500 RPM and at ambient temperature.

  3. Slowly increase the generator speed and observe the voltage using J 39200 .
  4. If the voltage is uncontrolled and increases above 16 Volts, repair or replace the generator.
  5. If the voltage is below 16 Volts, perform the following steps:
    6. • Increase the generator speed.
    • Connect the carbon pile.
    • Adjust the carbon pile in order to obtain maximum amperage output.
    • Maintain 13 Volts or more.
  6. Use and ammeter in order to check the amperage.
    7. • If the output is within 15 Amps of rated output, the generator is good.
    • If the output is not within 15 Amps of rated output, then repair or replace the generator.

Generator Assembly Bench Check UnRelease

This test requires both a fully charged battery and a generator test stand to operate the generator.


    Object Number: 1049 Size: SH
  1. Make connections as shown, except leave the carbon pile turned off. The ground polarity of the generator and battery must be the same. The battery must be fully charged. Use a 30-500 ohm resistor between the battery and the L terminal.
  2. Slowly increase the generator speed and observe the voltage.
  3. If the voltage is uncontrolled and increases above 16 volts, the rotor field is shorted, the regulator is not working properly, or both. A shorted rotor field coil can cause repeat regulator failure.
  4. If the voltage is below 16 volts, increase speed and turn on and adjust the carbon pile to obtain maximum amperage output. Maintain the voltage above 13 volts.
  5. If the output is with 15 amperes of the rated output, the generator is good.
  6. If the output is not within 15 amperes of the rated output, replace the generator.

Generator Assembly Bench Check CS-130

Tools Required

J 39200 Digital Multimeter

    Important: Perform the following inspection in order to verify operation of a repaired CS-130 generator:

  1. Mount the generator in a test stand. Ensure that the test stand is capable of driving a generator at 6500 RPM.

    2. Object Number: 1049 Size: SH
  2. Make the connections as shown.

    3. Important: Ensure that the batter is fully charged when making this test.

    Run the engine at 2500 RPM and at ambient temperature.

  3. Slowly increase the generator speed and observe the voltage using J 39200 .
  4. If the voltage is uncontrolled and increases above 16 Volts, repair or replace the generator.
  5. If the voltage is below 16 Volts, perform the following steps:
    6. • Increase the generator speed.
    • Connect the carbon pile.
    • Adjust the carbon pile in order to obtain maximum amperage output.
    • Maintain 13 Volts or more.
  6. Use and ammeter in order to check the amperage.
    7. • If the output is within 15 Amps of rated output, the generator is good.
    • If the output is not within 15 Amps of rated output, then repair or replace the generator.