Alternator: Testing and Inspection

1UR-FSE CHARGING: GENERATOR: INSPECTION

1. INSPECT GENERATOR BRUSH HOLDER ASSEMBLY





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

Standard length:

10.5 mm

Minimum length:

4.5 mm

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

2. INSPECT GENERATOR ROTOR ASSEMBLY





(a) Bearing inspection

(1) When rotating the bearing, check that the bearing does not become stuck and that there is no unusual noise.

If the bearing becomes stuck or there is unusual noise, replace the generator rotor assembly.

(b) Measure resistance





(1) Measure the resistance between the slip rings.

Standard resistance:

1.5 to 1.9 Ohms

If not within the specified range, replace the generator rotor assembly.

(2) Measure the resistance between the slip ring and rotor core.





Standard resistance:

1 MOhms or more

If not within the specified range, replace the generator rotor assembly.

(c) Measure diameter





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

Standard diameter:

14.2 to 14.4 mm

Minimum diameter:

14.0 mm

If not within the specified range, adjust the diameter with sandpaper (#400).

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

3. INSPECT GENERATOR ROTOR BEARING





(a) When rotating the bearing, check that the bearing does not become stuck and that there is no unusual noise.

If the bearing becomes stuck or there is unusual noise, replace the generator rotor bearing.