(3) Replace gasket between body and
(7) Check gear backlash by rocking the
spacer.
gears through the centerline connect-
(4) Replace bushings and gaskets if nec-
ing both shafts. This should be .001
essary.
to .003 inch.
(5) Inspect parts for cracks, breaks, wear,
(8) Check both the drive gear and the
or other damage. Replace parts that
driven gear in the pump body for the
are unserviceable.
correct clearance; use a dummy shaft
(6) Inspect gears for burrs, breaks, or
to hold gear in place as shown in figure
wear. Remove burrs or replace gears
42. This should not be over .003 inch.
if unserviceable.
(9) Remove cotter pin (32, fig. 41) from
(7) Replace crank and cam gears which
oil pressure relief valve (35) and dis-
show wear or damage if balancer as-
assemble.
sembly is replaced for any reason.
(10) Mark end of counterweight idler shaft
c. Assembly and Installation.
(76) and housing to locate proper
(1) Press bushing (42 ) into rear housing
radial positioning of counterweight
using a driver and an arbor press. It
idler shaft to housing at reassembly.
is important to line up bushing hole
(11) Drive out pin (73) holding counter-
radially with hole in housing before
weight idler shaft to housing with a
pressing bushing in.
prick punch. Drive out counterweight
Caution: Bushings must be pressed
idler shaft carefully.
in with the chamfered end contacting
(12) Remove staked setscrews (66) retain-
the housing. Do not hammer against
ing counterweight drive gear (72) to
end of bushing. Make certain that
the drive shaft (69).
end of bushings do not project past
(13) Remove nut (64) and pin (65) from
thrust face of housing.
drive shaft collar (71).
(14) To remove drive shaft (69) use a brass
(2) Install bushings (70 and 78) as above.
or aluminum drift and tap end of the
(3) Install plugs in balancer housing and
shaft lightly to prevent damage. Re-
t i g h t e n securely.
move counterweight drive gear (72).
(4) Reassemble tee, nipple, and elbow as-
(15) Straighten sheet metal locknut (61)
sembly (19).
and remove nut (51) and locknut. Re-
Caution: Do not try to remove and
move drive gear (62 ) only if service is
replace the drive gear from the drive
necessary.
shaft without removing the shaft as-
(16) Remove tube assembly (18) from tee
sembly from the housing. Driving
(24) to front idler boss. Disassemble
the gear on to the shaft while the
nipple (23), reducing bushing (21)
shaft is installed in the housing will
and elbows (20 and 22) from tee. Re-
damage rear bearing.
move tee (24) from balancer housing
(5) Position the keys (67 and 68) on the
(86). Remove all pipe plugs from bal-
drive shaft (69). Heat the drive gear
ancer housing. Press out front bush-
(62) to 200F. before pressing onto
ing (70 ) using an arbor press with a
shaft. Install one of the thrust wash-
driver. New bushings can be installed
ers (63), drive gear (62), sheet metal
with the same driver for the front and
locknut (61), hex nut (51) to the drive
intermediate case holes. Press out in-
shaft (69). Torque hex nut (51) to
termediate needle bearing or bushing
75 foot-pounds and bend locknut (61)
with same driver as above.
against flat on hex nut.
(17) Press out remaining bushings with a
Note. Use a pilot sleeve over the splined
p r o p e r driver.
end of the shaft when assembling to prevent
b. Cleaning and Inspection.
damage to rear bushing. Failure to use a
(1) Clean all metal parts with an approved
pilot sleeve will damage the shell of the rear
cleaning solvent and dry thoroughly.
bushing, causing a bearing failure.
(2) Steam clean all oil passages in hous-
(6) Slide drive shaft (69) into first hole
ing.
in housing (86). Install the other
76
AGO 8166A
