TM 9-2320-361-34 15-38. BORING CASE MAINTENANCE (Contd) f. Boring Gear and Case Installation 1. 2. 3. 4. 5. NOTE Assistant will help with steps 1 and 2. Position worm gear wheel (25) and boring case (17) on intermediate case (30). Install screw (26), new lockwasher (21), and jamnut (20) on boring case (17) and worm gear wheel (25). Install three screws (27), new lockwashers (23), and nuts (22) on boring case (17) and worm gear wheel (25). Install four new lockwashers (28) and screws (29) on boring case (17) and worm gear wheel (25). Install two felt pads (24) and retainer ring (16) on boring case (17) with four new lockwashers (15), screws (14), three screws (13), lockwashers (18), and nuts (19). 15-139