(7) Inspect the serrations in the blower timing
gears for wear and peening. Inspect gear teeth for
wear, chipping, or other damage. Back lash between
gear teeth should not exceed 0.004 inch. Replace
defective or damaged timing gears as a set.
(8) Inspect blower drive shaft serrations for
wear or other damage. Replace a damaged or bent
(9) Inspect the serrations inside the rotor
drive hub for wear or other damage. Replace a
defective drive hub.
(10) Inspect the blower drive coupling springs
and cam for wear and other damage. Replace defective
(11) Inspect the thrust washers. Replace worn
or scored washers.
(12) Inspect bearings for binding, wear, or
STEP 2. DISCONNECT SHUT-DOWN WIRE (NOT
scoring. Replace a defective bearing.
SHOWN) FROM AIR SHUT-DOWN VALVE
(13) Inspect the blower drive coupling support,
cam spring seats, and spring packs for wear or other
STEP 3. REMOVE AIR INLET HOUSING
damage. Replace any defective parts.
STEP 4. REMOVE BLOWER DRIVE.
(14) Inspect blower drive gear teeth for
STEP 5. REMOVE BLOWER ASSEMBLY
chipping, wear, or scoring. Replace a defective gear.
(15) Replace worn or excessively damaged air
Figure 17-1. Air inlet housing, blower and blower
inlet housing, blower, and blower drive parts.
drive assembly, removal and installation.
(3) Inspect the blower rotor lobes for burrs
(1) Reassemble the blower assembly in the
and scoring. If rotors are only slightly scored or burred,
reverse of the numerical sequence as illustrated on
clean them with emery cloth. Replace excessively
scored or burred rotors.
(a) Press oil seal (44) into the end plate
(4) Inspect rotor shaft serrations for wear
(37). Position the oil seal approximately .005 inch below
burrs, or peening. Replace defective rotor.
the finished face of the end plate. Install the remaining
(5) Inspect the inside surfaces of the blower
oil seals in the end plates in the same manner.
housing for burrs or scoring. Clean up slightly scored or
(b) The dowel pins located on end
burred areas with emery cloth.
plates (31 and 46), must project .380 inch from the flat
(6) Inspect inside face of each end plate. If
inner face and .270 inch from the outer face of the end
the finished face is slightly scored or burred, clean with