Generators & Regulators: Overhaul: Generator: Disassembly

Remove generator. Remove pulley nut. Remove pulley and collar from driveshaft. Pry off plastic cover that encloses rectifier and regulator/brush holder assemblies. Inspect cover for damage. Remove generator through-bolts. Remove bolts which secure rectifier assembly and regulator/brush holder assembly to slip ring end frame. See Figure -Figure .
To remove regulator/brush holder and rectifier assemblies, first melt solder of lead connecting regulator/brush holder assembly to rectifier assembly lead to stator. Do same to other rectifier assembly leads to stator, (as shown). Test each of three diodes of rectifier assembly for continuity. Connect ohmmeter probes on each side of diode. Retest by connecting ohmmeter probes reversely. See Figure and Figure .
If readings are same, replace rectifier. Mark a line perpendicular to crack between case of drive end frame and that of slip ring end frame. Pry open drive end frame from slip ring end frame. Remove collar. Remove fan. Separate rotor from slip ring end frame. Using an ohmmeter, test stator for ground. If reading is low, replace stator. Also, check stator for an open circuit by placing probes on two terminals. See Figure .
If reading is high (infinite), replace stator. Using an ohmmeter, test rotor for an open circuit. Check that there is continuity between slip rings. Standard resistance (cold) is 2.8 to 3.0 ohms. If there is no continuity, replace rotor. Using an ohmmeter, inspect rotor for ground. Ensure there is no continuity between rotor and slip ring. See Figure -Figure .