TM 5-3820-239-15
b. Disconnect the feed chain coupler links
3-28. Installation
a. Loop the feed chain around the top
by removing the cotter pins and the link side
tower sprocket (fig. 3-10) on the drill guide.
plates.
b. Carefully thread the chain under the top
c. Lift the feed chain off the tower sprockets
idler wheel, around the sprocket, and over the
and carefully remove it from the air feed motor
bottom idler wheel in the air feed motor
sprocket and the drill guide.
Caution: Make sure the feed chain engages
3-27. Cleaning and Inspection
properly with the sprocket to avoid binding.
a. Clean the feed chain with approved sol-
c. Thread the feed chain around the lower
vent. Dry thoroughly.
tower sprocket (fig. 3-10) and connect the
b. Inspect the feed chain carefully for brok-
coupler links to the drill mounting plate links.
en links. Repair or replace as necessary.
Install the cotter pins in the coupler links and
bend the ends over to secure the side `plates.
c. Coat the feed chain with oil to prevent
corrosion and insure smooth operation.
Section VIII. CENTRALIZER
the drill steel position when the arms are
3-29. General
closed. The arms can be manually opened by
The centralizer is mounted in a bracket at
use of a swing bolt and they will remain in
the lower end of the drill guide. It maintains
