TRUCK SERVICE MANUAL
FUEL SYSTEM
Fig. 5-31, F5141. Gear pump with integral cooling
Cleaning And Inspection
1. Check pump shafts for wear or scoring, discard if
Fig. 5-30, F5140. Tachometer and matching drive gears
damaged. Replace shaft If worn smaller than 0.4998 to
0.5001 inch [12.695 to 12.703 mm] diameter.
Right Hand And Left Hand Rotation Housings
2. Check gear width. See Table 5-5. If gears are
Do not use a right hand rotation fuel pump housing with a
scored or worn badly, the gears must be replaced.
left hand rotation gear pump. The fuel passage from the
gear pump to the fuel filter is located up and to the right
3. Check gear body and cover for scoring or wear,
of the main shaft in a right hand rotation housing.
replace parts as needed. Check gear pocket depth. See
(Looking at gear pump end of housing.)
Table 5-5. Fig. 5-32.
The fuel passage is located up and to the left of the main
4. Shaft bore in cover and body should be 0 5013 to
shaft In a left hand rotation housing.
0.5016 Inch [12.733 to 12.740 mm] I.D. In 3/4 inch
[19.05 mm] current cast Iron bearing gear pumps. If
GEAR PUMP AND PULSATION DAMPER
gears are removed from shaft, press
The gear pump draws fuel from the tank through a filter
and supplies the fuel to the fuel pump. Fuel at a given
Table 5-5: Gear Width And Pocket Depth - Fig. 5-32.
pressure is then routed to the injectors.
Pump Size Gear Width
Gear Pocket
Inch [mm]
Inch [mm]
Depth In. [mm]
Gear Pump
3/4
0.7483/0.7486
0.7478/0.7483
PT (type G) fuel pumps currently have gear pumps with
[19.05}
[19.006/19.014]
[18.994/19.006]
hollow idle shafts and the gear pump cover is drilled for
cooling as described under "Gear Pump"
Note: Special C.I.T.E. fuel gear pumps will have the BM
or AR number stamped on the side of the gear pump.
Caution: Engines with integral cooling gear pumps
(Fig. 5-31) must not be run with the fuel bleed hole
plugged.
Disassembly
1. Remove capscrews securing gear cover to gear
body.
2. Drive against dowels with flat end punch to remove
gear over from dowels In gear body. Discard gasket
Fig. 5-32, F523. Gear pump pocket depth
3. Lift drive and driven gears and shafts from gear
pump body.
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