TM 5-4310-379-14
5-13. Blower Assembly (Cont)
(h)
Place grease on bearings (20) and (21).
(i)
Using bearing installer, install bearings (21) over rear end of rotor shaft and into rear end plate (11).
(j)
Install bearing retaining rings (22) in rear end plate (11).
(k)
Using bearing installer, install bearings (20) over front end of rotor shaft and into front end plate (10).
(l)
Install bearing retainers (23) and secure with six screws (24) and lockwashers (25).
(m)
Install clean folded towel between the rotors and a towel between rotor and the housing to prevent
the rotors from turning.
(n)
Install shims (26) and two rotor timing gears (27) simultaneously on rotor shafts (15) and secure with
two timing gear retaining nuts (28) and lockwashers (29. Torque nuts to 60-80 lb-ft (81-108 Nm).
(o)
Remove towels from rotor and housing.
(p)
Aline blower assembly as follows (figure 5-12):
NOTE
When measuring clearances of more than .005 in. (.012 cm), laminated feeler gages that are made
up of .002 in. (.005 cm), .003 in. (.007 cm) or .005 in. (.012 cm) are more practical and suitable than a
single feeler gage.
1
Using feeler gages, check clearances between rotor lobes from both inlet and outletside of blower as
follows:
NOTE
If more or less shims are required, both gears must be removed from rotors. Placing a .003 inch
shim in back rotor gear will revolve rotor .001 in. (.002 cm).
a
The clearance between the leading edge of the upper rotor lobe and trailing edge lobe of the
lower rotor lobe should be between .002--.006 in. (.005-.015 cm), add shims on rotor shaft
between gears and bearings.
b
The clearance between trailing edge of upper and leading edge of lower rotor should be a
minimum clearance of .009 in. (.023 cm). If the clearance is not a minimum of .009 in. (.023
cm), add shims on rotor shaft between gear and bearings.
2
Recheck the clearances between the rotor lobes.
3
Check clearance between the end of each rotor lobe and the end plate, twelve measurements in all.
Refer to figure 5-12 for the minimum clearance.
4
Check clearance between each rotor lobe and the blower housing at both inlet and outlet side, twelve
measurements in all. Refer to figure 5-12 for the minimum clearance.
5
Install two new plugs in blower housing rotor adjusting holes
Change 1 5-40
