6-41. BLOWER DRIVE - Continued
b. Cleaning and Inspection.
Dry cleaning solvent P-D-680 is potentially dangerous. Avoid
repeated and prolonged breathing of vapors and skin contact
with the liquid. Do not use near open flame, arcing equipment or
other ignition sources. Always wear eye protection and
protective clothing. The flash point of P-D-680 is 100 to 138 deg.
F (38 to 59 deg. C).
(1) Clean all parts in dry cleaning solvent (Item 3, Appendix E) and dry thoroughly.
(2) Make sure oil passage in the blower drive gear support is clean.
(3) Replace worn thrust bearings.
(4) Use a micrometer and check the inside diameter of sleeve bearings (9) and outside diameter of
shaft of drive support. Replace parts if clearance exceeds 0.050 inch (1.27 mm). Press sleeve
bearings from bore of gear using a suitable driver.
(5) Press new sleeve bearings into bore of hub. Bearings must be pressed in flush to 0.010 inch (0.254
mm) below face of gear. Ream sleeve bearings to an inside diameter of 1.6260 to 1.6265 inch (41.3 to
41.31 mm). The bearing bores must be square with machined faces of the bolt bosses on the gear
within 0.003 inch (0.076 mm) total indicator reading and concentric with the outside diameter of the
(6) Inspect pins (15) and (16) in support. Pins must extend approximately 0.080 inch (2.03 mm) above
the threaded end of the support shaft.
(7) Inspect drive hub for wear and damage. Replace hub if necessary.
(1) Clamp the drive support (3) in a vise with soft jaws.
(2) Install one thrust bearing (13) on to support shaft (17) with the tangs on the bearing engaging the
holes in the support.
(3) Lubricate the hub of the drive support, sleeve bearings in gear, thrust bearings and thrust washer
(4) Slide the gear (14) on the support hub (11) with the flat side of gear down.
(5) Install second thrust bearing (13) on support with tangs on bearing facing away from the gear.
(6) Install thrust washer (1 2) with slots in washer engaging tangs on thrust bearing.
(7) Install lockwasher (10) and nut (11). Tighten nut to a torque of 50 to 60 lb ft (68 to 81 N.m). Bend
lugs on washer against flats on nut.