Alternator: Testing and Inspection

4GR-FSE CHARGING: GENERATOR: INSPECTION

1. INSPECT CLUTCH PULLEY

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





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

2. INSPECT GENERATOR BRUSH HOLDER ASSEMBLY

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





Standard length:

9.5 to 11.5 mm (0.374 to 0.452 in.)

Minimum length:

4.5 mm (0.177 in.)

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

3. INSPECT GENERATOR ROTOR ASSEMBLY

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





If necessary, replace the rotor bearing.

(b) Check the rotor for an open circuit.





(1) Using an ohmmeter, measure the resistance between the slip rings.

Standard resistance:





If the resistance is not within the specified range, replace the rotor assembly.

(c) Check the rotor for a short to ground.





(1) Using an ohmmeter, measure the resistance between the slip ring and rotor.

Standard resistance:





If the resistance is not within the specified range, replace the rotor assembly.

(d) Using vernier calipers, measure the slip ring diameter.





Standard diameter:

14.2 to 14.8 mm (0.559 to 0.583 in.)

Minimum diameter:

14.0 mm (0.551 in.)

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

4. INSPECT GENERATOR DRIVE END FRAME BEARING

(a) Check that the drive end frame bearing is not rough or worn.





If necessary, replace the drive end frame bearing.