What was found
DURING APPROACH, PILOT SELECTED GEAR DOWN, AND NOTICE LANDING GEAR INDICATOR DID NOT INDICATE THREE GREEN LIGHTS. PILOT DISCONTINUED APPROACH AND PERFORMED MANUAL GEAR EXTENSION; INDICATOR SHOWED 3 GREEN LIGHTS GEAR DOWN AND LOCKED. PILOT LANDED WITH NO FURTHER ISSUES. ACFT WAS FERRIED WHERE MAINTENANCE FOUND LEAKAGE AROUND DOWN CYLINDER PORT OF HYDRAULIC POWER PACK; MAINTENANCE R & R HYDRAULIC POWER PACK. PERFORMED GROUND GEAR SWINGS IAW MM 32-30-04, OPS CHECKED GOOD, AND PERFORMED OPS CHECK FLIGHT, SYSTEM CHECKED NORMAL.