Alternator: Testing and Inspection

1AR-FE BATTERY / CHARGING: GENERATOR: INSPECTION

1. INSPECT GENERATOR PULLEY WITH CLUTCH

(a) Hold the center of the generator pulley with clutch, and confirm that the outer ring turns counterclockwise and does not turn clockwise.





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If the result is not as specified, replace the generator pulley with clutch.

2. INSPECT GENERATOR DRIVE END FRAME BEARING

(a) Check that the generator drive end frame bearing is not rough or worn and that it rotates smoothly.





OK:

The bearing rotates smoothly.

If necessary, replace the generator drive end frame bearing.

3. INSPECT GENERATOR BRUSH HOLDER ASSEMBLY

(a) Using a vernier caliper, measure the length of the exposed brushes.





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Standard exposed length:

9.5 to 11.5 mm (0.374 to 0.453 in.)

Minimum exposed length:

4.5 mm (0.177 in.)

If the exposed length is less than the minimum, replace the brush holder assembly.

4. INSPECT GENERATOR ROTOR ASSEMBLY

(a) Check that the generator rotor bearing is not rough or worn.





If necessary, replace the generator rotor assembly.

(b) Check the generator rotor for an open circuit.

(1) Measure the resistance according to the value(s) in the table below.





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Standard Resistance:





If the result is not as specified, replace the generator rotor assembly.

(c) Check if the rotor is grounded.

(1) Measure the resistance according to the value(s) in the table below.





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Standard Resistance:





If the result is not as specified, replace the generator rotor assembly.

(d) Check the slip ring diameter.

(1) Using a vernier caliper, measure the slip ring diameter.





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Standard diameter:

14.2 to 14.4 mm (0.559 to 0.567 in.)

Minimum diameter:

14.0 mm (0.551 in.)

If the diameter is less than the minimum, replace the generator rotor assembly.