AN MD88 WAS DISPATCHED WITH AN INCORRECT REPAIR FOR A RPT OF EXCESSIVE NOSE GEAR VIBRATION.

Narrative

ACFT XYZ OF THE ACR FLEET ARRIVED AT MY GATE (LINE MAINT) IN ZZZ; US. 6 INBOUND WRITE-UPS. WENT THROUGH ALL WRITE- UPS WITH PLT. GOT TO THIS WRITE-UP: EXCESSIVE VIBRATION AND RATTLE FROM NOSEWHEELS ON TKOF ROLL THROUGH RETRACTION. PLT SAID VIBRATION WAS EXCESSIVE; BUT IT DIDN'T FEEL LIKE THE GEAR WAS COMING OFF. I PROCEEDED TO OPEN GEAR DOORS AND INSPECT TORQUE LINK BUSHINGS (WHICH IS A COMMON THING ON MD88). BUSHINGS CHKED GOOD AND THE REST OF THE GEAR. TIRES WERE WELL IN LIMITS; BUT 1 TIRE PRESSURE WAS LOW. SVCED TIRE TO CORRECT PRESSURE. SIGNED OFF GEAR. ACFT FLEW TO YYY FROM ZZZ WITH NO PROBS. FROM YYY BACK TO ZZZ -- CREW WROTE UP VIBRATION AGAIN. ACFT WAS LAID DOWN AND TORQUE LINK BUSHINGS WERE FOUND WITH PLAY AND REPLACED; ALONG WITH BOTH TIRES AND ALSO THE STEERING COLLAR WAS FOUND TO HAVE AN EXCESSIVE GAP. I FOLLOWED MAINT MANUAL FOR NOSEWHEEL SHIMMY AND IT SAYS TO CHK TORQUE LINK ASSEMBLY FOR LOOSE OR WORN BOLTS OR BUSHINGS AND CHK ALL BOLTS; WHICH I DID. FOLLOWING DAY; ABC OF THE FAA WANTED TO KNOW WHY I DIDN'T DO MORE. MY REPLY WAS PLT DIDN'T REALLY ELABORATE ON THE VIBRATION SO I FOLLOWED MAINT MANUAL; INSPECTED TORQUE LINKS (WHICH WERE GREASED THE PREVIOUS LEG); WHICH WERE FULLY GREASED BY BBB THE FLT LEG PREVIOUS; AND PROBABLY TOOK UP THE PLAY IN BUSHINGS; WHICH EXPLAINS WHY IT MADE 2 FLTS BEFORE IT WAS NOTICED AGAIN. THESE TORQUE LINK BUSHINGS SEEM TO BE A PROB ON MD88. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE ACFT ARRIVED WITH 6 LOG RPTS AND ALL WERE REVIEWED WITH THE CREW BEFORE WORK BEGAN. THE RPTR STATED THE TORQUE LINKS FELT OK FOR PLAY BUT HAD BEEN PREVIOUSLY GREASED AND THE GREASE PROBABLY TOOK UP THE EXCESSIVE PLAY IF THE TORQUE LINK BUSHINGS WERE ACTUALLY THE CAUSE OF THE VIBRATION. THE RPTR SAID THE CORRECTIVE ACTION FOR THIS RPT WAS TORQUE LINK BUSHING REPLACEMENT AND BOTH NOSE TIRES REPLACED. THE RPTR SAID THE NOSE GEAR TORQUE LINK BUSHINGS EXPERIENCE HVY EXCESSIVE WEAR AND ARE A CHRONIC PROB. THE RPTR STATES THE FAA HAS ASSIGNED A PENALTY FOR THE RPTR'S ACTION.