TM 10-3930-659-34 5-9. TRANSMISSION CONTROL VALVE MAINTENANCE (Con’t). 18. Remove piston (71) and preformed packing (72) from cylinder (73).  Discard preformed packing. 19. Remove pilot orifice (83), vent plug (82), and piston (80) from cylinder (73). 20. Remove preformed packing (81) from vent plug (82).  Discard preformed packing. 21. Remove retaining ring (79), guide ring (78), preformed packing (77), and bushing (75) from cylinder (73). Discard retaining ring and preformed packing. 22. Remove two preformed packings (74 and 76) from bushing (75).  Discard preformed packings. 23. Remove  piston  (85)  and  spring  (84)  from  valve block (31). 5-68