TM 5-3820-245-14&P
B. Disassembly Feed Ram Assembly (figure 6-23)
1. Set feed ram assembly on some type of rack to provide a good working height.
2. Remove transfer tube clamps, split flange clamp halves and transfer tube assembly. Remove O-Ring
located in tip end of transfer tube assembly.
3. Remove the 12 capscrews from the feed ram cap. Slide cap off end of barrel. Remove O-Ring and
backup ring located inside cap. Remove lock ring by lifting the ring end up with a screwdriver and coiling it
out of the ring groove and off end of barrel. Slide retainer off end of barrel.
4. Loosen nuts on saddle and slide saddle off end of barrel.
5. Remove all bolts and nuts from working barrel braces and remove braces.
6. Remove barrel support from barrel by turning support counterclockwise. Remove O-Ring and backup ring
as located inside support.
7. Push on auger end of kelly bar until piston at tip end is exposed. Continue pushing bar until approximately
8 inches of kelly bar is exposed.
8. Remove piston rings with a ring expander tool.
9. Locate the piston pin in top end of piston. Head of pin will be flush with O.D. of piston, but can usually be
located by discoloration. The general location will be marked by a center punch mark on the top end of the
position. Drill down through wall of piston plug. This will cause an internal pressure leak if plug is reused.
Drill only deep enough to remove pin. Screw piston plug out of piston.
10. Using a plastic or rawhide hammer, knock piston back towards auger end of bar until it slides off the
bearing assembly.
11. Remove cotter pin and piston nut. Remove piston bearing and bearing cup with a bearing puller. Slide
piston offer end of kelly bar. Pull bar out either end of barrel.
NOTE: Wrap the bar end that will be rubbing the I. D. of the barrel while being removed to protect
barrel wall from possible damage. Pick up the exposed end of bar slightly during removal to
relieve the heavy metal-to-metal contact between kelly bar corners and barrel wall.
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