BEARING-PLNTY-YM 3759982 - Caterpillar

Illustration 1 g00720928
(1) Slip rings (2) Rotor (3) Rotor shaftField Winding Continuity Test
Set the multimeter to the 200 ohm resistance scale. Measure the resistance between the slip rings (1) .
The resistance between the slip rings (1) should be within the following values.Resistance of field winding at 27 °C (81 °F) 9X-6796 Alternator Gp ... 1.7 to 1.8 Ohms 9X-9096 Alternator Gp ... 1.7 to 1.8 Ohms 121-4134 Alternator Gp ... 1.7 to 1.8 Ohms 121-4135 Alternator Gp ... 1.7 to 1.8 Ohms 113-1379 Alternator Gp ... 1.7 to 1.8 Ohms 125-9597 Alternator Gp ... 1.7 to 1.8 Ohms 107-7977 Alternator Gp ... 9.5 to 10.7Ohms 132-2156 Alternator Gp ... 9.5 to 10.7Ohms
Replace the rotor (2) if the measurement is incorrect.Field Winding Ground Test
Set the multimeter to the 20 M ohm resistance scale. Measure the resistance between one of the slip rings (1) and the rotor shaft (3) .
The multimeter reading should be greater than 100 K Ohms(0.100 M Ohms).
Replace the rotor, if the multimeter reading is low. Low resistance indicates undesired continuity between the field winding and the rotor shaft.
Repeat steps 1 through 3 for the other slip ring (1) .