What was found
CLIMBING OUT THROUGH 18,000 FT, RECEIVED GEN 1 OFF ALERT. IAW QRH, ATTEMPTED ONE RESET, DID NOT HELP. VOLTS SHOWED 0, HZ 400. THEN GEN 3 OFF ALERT, TRIED RESET, NO HELP. VOLTS 0, HZ 400. THEN TR3 OFF ALERT SHOWED. THEN ELEC ALERTS LEVEL 2 ALERT. DUMPED 21.6K FUEL AND RTB. FOUND CAC HAD WATER INTRUSION. FOUND #3 GCU FAILED. REMOVED AND REPLACED GCU #3 REF. MM 24-21-03-4. OPS CKS NORMAL. HAD ENGINE RUNS PERFORMED, #1 & #3 GENERATORS , & TR'S OPS CHECKS NORMAL. REF. MM 24-21-03-4, & 24-31-01-2. ALL INDICATIONS NORMAL AND ALL FAULTS CLEARED. A/C OK FOR SERVICE. SDR INFO, GENERATOR CONTROL UNIT, P/N 750864D, S/N 0399, MFG SUNSTRAND.