Alternator: Testing and Inspection

2GR-FE CHARGING: GENERATOR: INSPECTION

1. INSPECT GENERATOR WITH CLUTCH PULLEY

(a) When rotating the generator pulley, check that it turns counterclockwise and does not turn clockwise.





2. INSPECT GENERATOR BRUSH HOLDER ASSEMBLY

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





Standard exposed length:

10.5 mm (0.413 in.)

Minimum exposed length:

4.5 mm (0.177 in.)

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

3. INSPECT GENERATOR ROTOR ASSEMBLY

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





If necessary, replace the generator rotor.

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





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

Standard resistance:

2.3 to 2.7 Ohms at 20°C (68°F)

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

(c) Check the generator rotor for a short circuit.





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

Standard resistance:

1 MOhms or higher

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

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





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.

4. INSPECT GENERATOR DRIVE END FRAME BEARING

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





If necessary, replace the generator drive end frame bearing.