PWR LEVERS STUCK ON FINAL APCH.

Narrative

ON COUPLED APCH RWY 4F TO EWR; ACFT STARTED TO GET SLOW. PUSHING THE THROTTLES DID NOT MOVE THEM. THEY APPEARED STUCK DUE TO INTERLOCK OR AUTOTHROTTLE CLUTCH. DISENGAGED AUTOTHROTTLE; THEN VIGOROUSLY PUSHED AND PULLED THROTTLES TILL THEY BROKE FREE. DSNDED BELOW GS TO MAINTAIN SPD AND LANDED NORMALLY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR FLIES THE B-737-300 FOR A MAJOR UNITED STATES ACR ON DOMESTIC RTES. HE HAS NEVER SEEN A PROB LIKE THIS BEFORE. HE DOES NOT THINK THAT THIS COULD HAVE BEEN CAUSED BY ICE AS THE THROTTLES WERE MOVING PROPERLY EARLIER IN THE APCH. THE LOGBOOK WAS WRITTEN OFF AS 'BITE CHK OK;' BUT THE ACFT WAS THEN TAKEN OTS FOR FURTHER TESTING. THE RPTR HAS EXTRACTED A PROMISE FROM HIS DIRECTOR OF OPS TO GET SOME FEEDBACK ON WHAT CAUSED THIS ANOMALY; AND HE WILL PASS THIS INFO ON TO THE ASRS. THE THROTTLES WERE AT OR NEAR IDLE WHEN THEY STUCK. THE RPTR THINKS THAT HE BROKE THEM LOOSE GOING TOWARDS THE CLOSED POS; THEN FORWARD. HE DID NOT ASK FOR HELP FROM HIS VERY NEW FO. THE RPTR BELIEVES THAT HE USED 'ABOUT 60 LBS FORCE' TO BREAK THE THROTTLES LOOSE.