TM 5-3810-300-24&P-3
1.7.4
Assemble Idler Gear, Hub and Bearing Assembly
Refer to Fig. 3 and assemble bearing components in
their original positions (refer to identification marks made
during disassembly) as outlined below:
1. Support the idler gear, shoulder down; on the bed of
an arbor press and start the outer bearing race
squarely into the bore of the gear. Then, press the
bearing race tight against the shoulder of the gear,
using a steel plate between the ram of the press and
the bearing race.
2. Support one bearing cone, numbered side down, on
bed of arbor press and lower the idler gear and
bearing cup assembly down over the bearing cone.
Fig. 2 - Pressing Hub Out of Bearing
3. Lay spacer ring on face of bearing cone.
2. Clean the idler gear and bearing assembly with fuel
oil and dry it with compressed air.
4. Place the second bearing cone, numbered side up,
in the idler gear and bearing cup assembly and
3. Place the idler gear and bearing assembly in an
against the spacer ring.
arbor press with the bearing cone or inner race
supported on steel blocks as' shown in Fig. 2. While
5. Then, position the idler gear hub over the bearing
rotating the gear assembly, press the hub out of the
cones so that the oil hole in the hub is 180 from the
bearing. Remove the gear assembly from the arbor
gap in the spacer ring.
press and remove the bearing cones and spacer.
6. Press the hub into the idler gear bearing cones,
NOTE: Component parts of the idler gear
while rotating the gear (to seat the rollers properly
bearing are mated; therefore, match-mark the
between the cones) until the face of the hub which
parts during disassembly to assure they will be
will be adjacent to the cylinder block end plate is
reassembled in their original positions.
flush with the corresponding face of the bearing
4. Tap the bearing cup (outer race) from the idler gear
cone. The bearing cones should be supported so as
by using a brass drift alternately at four notches
not to load the bearing rollers during this operation
provided around the shoulder of the gear.
Inspect Idler Gear and Bearing
7. Prior to installing and securing the bearing retainer,
check the preload of the bearing assembly as
Wash the idler gear, hub, and bearing components
outlined below.
thoroughly in clean fuel oil and dry with compressed air.
Inspect all parts for wear.
Check Pre-Load of Bearing
Inspect bearings carefully. Wear, pitting, scoring or flat
The rollers of the bearing are loaded between the
spots on the rollers or races are sufficient cause for
bearing cup and bearing cones in accordance with
rejection and the bearing assembly must be replaced.
design requirements to provide a rigid idler gear and
bearing assembly. As the bearing cones are moved
Check the idler gear hub and spacer for wear or
toward each other in a tapered roller bearing assembly,
damage.
the rollers will be more tightly held between the cones
Examine the gear teeth for evidence of scoring, pitting
and cup. In the idler gear bearings, a slight pre-load is
and wear. If severely damaged or worn, replace the
applied by means of a
gear. Also, inspect other gears in the gear train.
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