What was found
(CAN) DURING HEAVY MAINTENANCE, LT FLAP TRACKS NR 4 AND 5 WERE REPLACED WITH SERVICEABLE FROM STOCK. MAINTENANCE THEN OBSERVED THAT THE FLAP CARRIAGES 4 &5 WOULD NOT ROLL ON THE FLAP TRACKS NR 4 AND 5 AS THEY SHOULD, AND SATISFACTORY ADJUSTMENT/FUNCTION COULD NOT BE ACHIEVED. THE FLAP TRACKS WERE REPLACED A SECOND TIME WITH SAME TWO PART NUMBERS SERVICEABLE FROM STOCK AND FLAP CARRIAGES FUNCTIONED NORMALLY WITH NO FURTHER ISSUES.