Note.—For complete instructions regarding disassembly of the breech mechanism see page 19. 4. Remove trigger-shaft detent split pin and trigger-shaft detent by drawing it out of the breechblock to the right. 5. Remove trigger shaft by prying gently straight down with screw driver or similar tool. Keep breechblock supported for all succeeding operations. 6. Remove operating handle by sliding to the right and off operating shaft. 7. Remove operating shaft by sliding to the left. 8. Raise breechblock as far as possible (about 3-8 inch), move bottom part of operating arm to the rear, and remove operating arm. 9. Remove breechblock by sliding down free of breech ring. 10. Remove extractors by sliding toward center line of gun. VII. To Replace Piston Rod Gland Packing. (Packing, 4 rings, 5-16-inch square Garlock hydraulic packing.) (Gun in battery or cylinder removed.) 1. Remove lower split pin from gland lock, swing gland lock up out of notch in gland. 2. Unscrew gland with special wrench and slide forward on rod. 3. Remove packing with bent wire. 4. Insert five rings of new packing, one ring at a time, and push each ring home with packing tool of copper or hardwood to fit into gland recess. Break joints in rings and tap packing tool lightly with hammer to drive each ring of packing home. 5. Screw up gland by hand and not more than three additional notches with wrench so that gland lock will catch and replace split pin. Note.—For the first few rounds after inserting new packing there will be some leakage at gland and occasional tightening will be necessary. Gland should not be screwed up tight with a wrench, as it can be made sufficiently tight by hand to prevent leakage if properly packed. VIII. To Remove Wheel. 1. Raise and support carriage under equalizing gear near each end (about 12” each side of center.) 2. Disengage hubcap latch; unscrew and remove hubcap. 3. Disengage wheel fastening plunger and remove wheel fastening. 4. Remove wheel. IX. To Remove Shields. A. Top shield.—1. Remove four ⅜” pins, two ⅜” locking pins, and lift off shield. B. Apron.—1. Remove four ⅜” hinge pins and remove apron. C. Cradle Shield.—1. Remove two 3/32” split pins, nuts and bolts. On carriages number 625 to number 678 inclusive, remove two cradle shield extensions. D. Main Shield, left.—1. Remove six ½” bolts from shield bracket outer left. 2. Remove three ⅜” bolts from shield socket, inner left. 3. Lift off shield. Main Shield, right—1. Remove right wheel (see VII). 2. Remove ½” pin from brake band end, remove adjusting nut and force (by hand) brake band out of position, to clear main shield, right. 3. Remove four ½” bolts from shield bracket, outer right, and two ½” bolts from brake lever bracket. Remove two 2/16” bolts from tool and remove tool carrier. Remove three ⅜” bolts from shield bracket, inner right. 4. Lift out shield. X. To Remove Spring Cylinder.