What was found
RED GEAR UNSAFE AND HYD PRESS ON LIGHT REMAINED ILLUM AFTER GEAR RETRACTION ON TAKEOFF. CKLST ISOLATED PROBLEM TO GEAR CONTROL CB, WHICH GAVE GREEN MAINS/RED UNSAFE BUT NO HYD LIGHT W/ CB PULLED. 3 GREEN/NO RED W/CB RESET AND HANDLE DOWN. FOUND LT UPLOCK ROLLER FULL OF SAND REMOVED SAND CLEANED AND LUBED ROLLER, OPS CHECK GOOD AT THIS TIME ALL WORK DONE IAW CESSNA 560 MM CHAPTER 32-31-05.