Generator Inspection

Check the rotor for an open circuit.

1. Measure the resistance between the slip rings.
   

   Standard resistance:

   1.8 to 2.8 Ωat 20°C (68°F)
   

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

Check if the rotor is grounded.

1. Measure the resistance between the slip ring and rotor.
   

   Standard resistance:

   10 kΩ or higher
   

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

Check that the slip rings are not rough or scored.
If rough or scored, replace the rotor assembly.

Using a vernier caliper, measure the slip ring diameter.

Standard diameter:

15.3 to 15.5 mm (0.602 to 0.610 in.)

Minimum diameter:

14.9 mm (0.587 in.)

Inspect the positive (+) rectifier.

HINT:

Inspect the positive terminal after pulling it up.

1. Using an ohmmeter, connect one tester probe to the positive (+) terminal and the other to each rectifier terminal.
   

2. Reverse the polarity of the tester probes and repeat the step above.
   

3. Check that one shows a resistance of below 1 Ω and the other shows a resistance of 10 kΩ or higher.
   If the result is not as specified, replace the generator stator sub-assembly with rectifier.
   

Inspect the negative (-) rectifier.

1. Using an ohmmeter, connect one tester probe to the negative (-) terminal and the other to each rectifier terminal.
   

2. Reverse the polarity of the tester probes and repeat the step above.
   

3. Check that one shows a resistance of below 1 Ω and the other shows a resistance of 10 kΩ or higher.
   If the result is not as specified, replace the generator stator sub-assembly with rectifier.
   

Inspect the stator coil for an open circuit.

1. Measure the resistance between the rectifier terminals.
   

   Standard resistance:

   Below 1 Ω
   

   If the result is not as specified, replace the generator stator sub-assembly with rectifier.
   

Using a vernier caliper, measure the exposed brush length.

Standard exposed length on new brush:

13.2 mm (0.520 in.)

Minimum exposed length:

6.0 mm (0.236 in.)

When rotating the outer part of the pulley, check that it is as follows: 1) rotating it clockwise causes the inner and outer part of the pulley to turn together; and 2) rotating it counterclockwise causes only the outer part of the pulley to turn.