What was found
LOSS OF POTABLE WATER PRESSURE, FLIGHT DIVERTED. FOUND PRESELECT OVERFLOW VALVE STUCK OPEN. POSITIONED VALVE IN CLOSED POSITION. WATER PRESSURE NORMAL. NEED TO MANUALLY CLOSE AT EACH DEPARTURE. OVERFLOW VALVE OPENS & CLOSES OK FROM REAR SERVICE PANEL. WHEN SERVICING FROM FWD PANEL VALVE WILL NOT CLOSE WHEN PRESELECTED WATER LEVEL REACHED. REPLACED RELAY K38013 NO HELP. TAPPED ON VALVE MOTOR. TAPPED ON OVERFLOW VALVE MOTOR AND MOTOR CLOSED. R & R OVERFLOW VALVE AND OPS CHECK NORMAL.