TM 5-3810-300-24&P-3
1.7.6
BLOWER DRIVE GEAR AND SUPPORT ASSEMBLY
The blower drive gear is mounted on the blower drive
gear support and in addition to driving the blower, drives
the governor, water pump and fuel pump. The drive is
cushioned by a spring-loaded flexible coupling which
insures a uniform rotation of the blower rotors (Figs. 1
and 5).
The left-hand helix blower drive gear is driven by the
camshaft gear on RA engines and the balance shaft gear
on RB engines. The right-hand helix blower drive gear is
driven by the camshaft gear on RC engines, and the
NOTE: The 39 tooth and the 40 tooth blower
drive gears are interchange-able, however, the
governor will have to be adjusted to
Fig. 1 - Typical Blower Drive Gear and
compensate for the approximately 2.5 per cent
Support Assembly
change in the governor drive speed.
47
Cover--Blower Drive
73
Lock Washer
A new blower drive support assembly has replaced the
51
Seal--Drive Cover
75
Pipe--Drive Bearing Oil
former assembly (Fig. 2). The new and former blower
52
Clamp--Cover Seal
76
Elbow--Oil Pipe
drive assemblies are different in that the flanged bearing,
53
Gear--Blower Drive
79
Shaft--Blower Drive
54
Hub--Drive Gear
80
Ring--Blower Drive
which also served as a thrust surface, has been replaced
55
Lock Ball
Shaft
by a new bearing. The inner bearing of the new
56
Washer--Drive Gear
81
Hub--Blower Rotor Gear
assembly protrudes slightly from the inner face of the
Hub Thrust
83
End Plate--Cylinder
support to facilitate installation of and to serve as a pilot
57
Nut--Drive Gear Hub
Block-Rear
58
Lock Washer
91
Housing--Flywheel
for the thrust washer.
59
Bearing--Drive Gear Hub
92
Cover--Flywheel
61
Support--Drive Gear Hub
Housing (Small Hole)
Remove and Install Blower Drive Shaft
63
Gasket
93
Gasket--Cover
64
Bolt--Drive Gear
94
Bolt--3/8"-16 x 7/8"-
Hub Support
Cover
If the blower drive shaft is not broken, it may be removed
67
Support--Drive Coupling
95
Bolt--3/8"-24 x 5"-
as follows:
68
Cam--Drive Coupling
Cover
71
Retainer--Drive Coupling
96
Lock Washer
1. Remove the six bolts (94 and 95) that secure the
72
Bolt--Drive Coupling
102
Thrust Washer
flywheel housing small hole cover (92), Fig. 1.
or other malfunction. Inspect the blower drive, blower
rotors and the housing before replacing the drive shaft.
2. Refer to Fig. 4 and remove the snap ring and pull the
Refer to the blower inspection procedure in Section 3.4.
blower drive shaft out of the drive assembly.
Reverse Steps 1 and 2 for the installation of the blower
NOTE: Some shafts have a tapped hole in the
drive shaft.
end which can be used as an aid in removing
the shaft.
Remove Blower Drive Gear and Support Assembly
(Flywheel Housing Removed)
If the blower drive shaft is broken and it is not possible to
remove all of the pieces, it will be necessary to remove
Removal of the flywheel housing is not necessary when
the blower, see Section 3.4.
removing the blower drive gear, however, an inspection
of the gear train is advisable when any one of the gears
A broken drive shaft indicates an unusual loading which
requires service. The procedures for the removal of the
may have been caused by a bearing failure
flywheel and flywheel housing are found in Sections 1.4
and 1.5.
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