What was found
ON APPROACH INTO KMIA, THE NOSE GEAR DID NOT EXTEND WHEN THE GEAR WAS LOWERED. GEAR WAS RECYCLED PER CCIA AOM AND THE RED LIGHT STAY ON, NO GREEN LIGHT. EXECUTED A GO AROUND AND MANUALLY LOWERED THE NOSE GEAR, CONFIRMED GEAR DOWN AN ADVISED ATC, DECLARED EMERGENCY AND AIRCRAFT LANDED WITHOUT INCIDENT. AIRCRAFT WAS INSPECTED AND THE NOSE LANDING GEAR DOWN LOCK SWITCH WAS REPLACED. ALSO, LUBED THE NOSE LANDING GEAR AND PERFORMED GEAR EXTENSION AND RETRACTION TEST. OBSERVED NORMAL OPERATIONS FOR ALL TEST AND NO DEFECTS NOTED IAW B727 MM 32-31-15, 12-00-0 AND 32-33-0 PAGE 502 AND THE AIRCRAFT RETURNED TO SERVICE.