TM 10-3930-669-34 15-3. STACK VALVE REPLACEMENT/REPAIR (CONT). (6) Install  four  poppet  valves  (74,  75,  76,  and  77)  and  springs  (73)  in  pivot  valve  (66),  tilt  valve  (67),  shift valve (69), and lift valve (70). (7) Install six preformed packings (72) in pivot valve (66), tilt valve (67), shift valve (69), and lift valve (70). (8) Position inlet (65), pivot valve (66), tilt valve (67), mid-inlet (68), shift valve (69), lift valve (70), and outlet (71). 15-22