TRUCK SERVICE MANUAL
ENGINE
Fig. 9-1, (N10903). Fuel pump or compressor drive
2. Do not spin bearings before cleaning. Do not spin by
housing must be scrapped. Bore of housing must be
force of air. Hold both races while drying with clean,
clean before pressing bearing in place.
compressed air. The following defects cause bearings to
be rejected for further use:
Thrust Washers
In installation of thrust washers on accessory drives,
a. Broken or cracked race.
thrust side of washers is installed away from housing.
b. Dented shields or seals.
Thrust side is identified by grooves. Steel backing
c. Cracked or broken separators.
against the cast iron housing will reduce the possibility of
d. Flaked areas on balls, rollers or raceways.
thrust washers' turning. Improper installation of these
e. Broken or cracked balls or rollers.
washers will result in excessive wear and increased end
f. Bearings that have been overheated. These bearings
play, which causes early failure of accessory drive
are generally darkened to a brownish-blue or blue-black
assembly.
color.
g. Bearings whose raceways are indented or "brinelled"
Fuel Pump Or Compressor Drive
by impressing balls or rollers into the races.
DISASSEMBLY AND INSPECTION
Oil Seals
1. Remove drive shaft locknut (9, Fig. 9-1), using ST-
Effectiveness of the seal depends on surface where seal
850 or ST-1249 Coupling puller, pull coupling (10) from
seats. Always check hub sleeve surface for wear and
shaft (7).
replace sleeve if necessary before installing new seal.
Immediately before installing seals, always lubricate
Press shaft and gear assembly from housing (5), press
with clean lubricating oil.
shaft (7) from gear (2), and remove keys (11) from shaft
(7).
Bores In Housing
Note: A splined coupling is used on air compressor
Bearings or bushings must not turn in housing retaining
drive. A buffer type coupling is used on fuel pump and
bore. If old bearing has turned and ruined housing, the
magneto drive.
2. Inspect bushing in drive housing. Replace if worn
beyond specifications as shown in Table 9-1(4). Replace
thrust washers if worn or damaged.
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