What was found
FAR 1135.415 REPORT. PILOT REPORTS "LH GENERATOR DROPPED OFFLINE CAUSING A MASTER CAUTION. TRIED ONE RESET, BOTH VOLTMETERS STARTED FLUCTUATING. TURNED LH GEN BACK OFF AS PER CHECKLIST". MAINTENANCE INSPECTED LH STARTER/GENERATOR AND CONTROL SYSTEM. WHEN CENTER FLOORBOARD WAS REMOVED FOR ACCESS, FOUND LIQUID ON THE LH GCU AND SURROUNDING AREA OF THE BELLY FROM SUSPECTED SPILL IN THE CABIN. REMOVED LH GCU, CLEAN LOCAL AREA AND GCU CONNECTOR. REPLACED LH GCU, OPERATIONAL CHECKS SATISFACTORY.