What was found
SEA FLIGHT NR 2390: LANDING GEAR DID NOT RETRACT AFTER TAKE-OFF. ALL 3 GEAR UNSAFE INDICATION ON WHILE GEAR HANDLE IN THE UP POSITION. MAINTENANCE INTERROGATED PSEU AND FOUND NW CENT UNRREASONABLY FAR. CHECKED NW CENT PROX SW GAP AND FOUND IT TO BE OUT OF LIMITS (.068 INCH) IAW AMM 32-61-06. ADJUSTED GAP IAW AMM TASK 32-61-06-830-801. PSEU NW CENT READS OK. GEAR SWING COMPLETE. NO PARTS REPLACED. AIRCRAFT RETURNED TO SERVICE.