7-19. Drifter Drill Repair
(17) Remove grease fitting (33) from spacer cover
(18) Remove bearing cone (34) from carrier (35).
(1) Remove drifter drill (see paragraph 7-7).
(19) Remove two dowel pins (36), then remove car-
Warning: Dry cleaning solvent P-D-680 is toxic and
flammable. Wear protective gloves and use in a well venti-
(20) Press two shafts (37) out of flange (38). Sepa-
lated area. Avoid contact with skin, eyes, and clothes and
rate upper plate (39), flange (38), motor housing (40), two
do not breathe vapors. Do not use near open flame or ex-
bearings (41) and spacer (42), air motor gear (43), lower
cessive heat. The flash point is 100-138 degrees F (38-50
plate (44), and two gears (45).
degrees C). If you become dizzy while using cleaning sol-
(21) Remove bearing cone (46) from carrier (35).
vent, get fresh air immediately and get medical aid. If con-
(22) Remove three gears (47) from shafts (48).
tact with eyes is made, wash your eyes with water and get
medical aid immediately.
(23) Remove nut (49) from each shaft (48) and press
shafts out of carrier (35).
Note: Clean exterior of (drifter drill before disassembly.
(24) Remove bearing cup (SO) from main housing
Use a babbitt hammer 10 drive off the heavier exterior parts.
Handle parts carefully. Hardened parts might chip or break if dropped
on a hard surface. Other parts may be damaged by improper handling.
securing manifold (54) to main housing (51). Remove
Clean disassembled parts in a solvent. Probe ports to loosen and remove
manifold and gasket (55). Discard gasket and lockwashers.
(2) Unscrew front cap (1) and remove bushing (2)
securing cover (58) to main housing (51). Remove cover
and striker bar (3).
and gasket (59). Discard gasket and lockwashers.
(3) Remove gland plug (4) from backhead (5).
(27) Remove grease fitting (60) from main housing
(4) Remove air tube (6). washer (7). packing (8),
and O-ring (9). Discard packing and O-ring.
b. Inspection and Repair.
(5) Remove four nuts (10) and side rods (11).
(1) Inspect all bushings, bearings, cups, and cones
(6) Lift off backhead (5) evenly and straight, being
in accordance with TM 9-214.
careful not to disturb upper distributor (12).
(2) If replacement is required, press two bearings
(7) Remove seal (13) and muffler (14). Discard
(61) and bushing (62) out of each gear (45) and replace.
(3) If replacement is required, press bushing (03)
(8) Remove and separate upper distributor (12),
out of each gear (47) and replace.
piston (15), cylinder (16), lower distributor (17), and lower
(4) Check striking face of piston (15). If wear is
greater than 0.030 in., grind striking fact square. If wear
(9) Remove and discard two O-rings (19) from pis-
is greater than 0.050 in., replace piston.
(5) Check clearance between piston head and cyl-
(10) Remove and discard two upper (20) and two
inder (16). If total clearance is greater than 0.015 in., re-
lower (21) packings from cylinder (16).
place piston, cylinder, or both.
(11) If damaged, remove spring pin (22) from upper
(6) Check clearance betwccn piston stems and up-
distributor (12) and remove spring pin (23) from cylinder
per and lower distributors (12 and 17). If total clearance
is greater than 0.006 in., replace piston, distributors, or all
(12) Turn drifter drill so that front cover (24) faces
(7) Check for gaulding and burning in the upper
(13) Remove front cover (24).
and lower distributors (12 and 17) and the cylinder (16).
Hone to clean or replace.
(14) Remove bearing cup (25), retainer (26). and
spring washer (27) from front cover (24).
(8) Carefully check air tube (6) for splits, cracks.
scoring, or excessive wear. particularly in the first 4 in.
(15) Remove bearings (28).
where air tube contacts striker bar. Replace cracked, split,
(16) Remove spacer cover (29), gear (30), air motor
scored, or worn air tube.
assembly (31), and roller bearings (32). If air motor assem-
(9) Inspect plates (39 and 44) for sharp edges and
bly is stuck, lay the drifter drill on its side and gently tap
wear. Remove all sharp edges and hone to clean.
out the air motor assembly with striker bar (3).