Visually examine condition and length of brushes and check
for free movement of brushes in brush box holder (less than
0.75in / 19mm)
Rotate alternator visually checking slip rings for grooves
and burns
Connect AVO to field circuit rotate rotor through one
revolution and measure field resistance.
Field resistance should be 16-20 ohms
If high clean slip rings
If low alternator to be changed
Check bearings
Reconnect rotor field cables, replace cover
Replace inspection cover ensuring cover joint is in good
condition
Replace belts on pulley and tension correctly
Check output with tong tester
Fault Finding AC8 / RUG 11A / 14A
Check for missing or slack belts
Service as per depot exam
Remove AC connection covers, start both engines, run at
idling speed, use a proven 24 volt x 2.8W test lamp, connect
between terminals F+ and F- to check rotor field circuit
supply. Lamp should light, if no light RUG unit should be
changed (no self exciting circuit)
Connect test lamp between AC outputs, if lamp lights but no
charging output RUG defective (main rectifier defective)
