DETROIT DIESEL 53
Fuel Pump 2.2
1. Remove the eight cover bolts and withdraw the pump
cover from the pump body. Use care not to damage the
finished faces of the pump body and cover.
2. Withdraw the drive shaft, drive gear and gear retaining
ball as an assembly from the pump body.
3. Press the drive shaft just far enough to remove the steel
locking ball. Then, invert the shaft and gear assembly and
press the shaft from the gear. Do not misplace the steel
ball. Do not press the squared end of the shaft through the
gear as slight score marks will damage the oil seal contact
surface.
4. Remove the driven shaft and gear as an assembly from
the pump body. Do not remove the gear from the shaft.
The driven gear and shaft are serviced only as an assembly.
5. Remove the relief valve plug.
6. Remove the valve spring, pin and relief valve from the
valve cavity in the pump body.
Fig. 4. Removing Oil Seals
7. If the oil seals need replacing, remove them with tool J 1508-7, as shown in Fig. 4, by clamping the pump
body in a bench vise and screwing the threaded end of the tool shaft into the outer oil seal (seal nearest to the
bolting flange). Then tap the pilot end of the shaft with a hammer to remove the seal. Repeat this operation to
remove the inner oil seal.
Inspection
Clean all of the parts in clean fuel oil and dry them with compressed air.
Oil seals, once removed from the pump body, must be discarded and replaced with new seals. The lips of the
oil seals must fit snug around the pump shaft and must be free of nicks or cracks.
Check the pump gear teeth for scoring, chipping or wear. Check the ball slot in the drive gear for wear. If
necessary, replace with a new gear.
Inspect the drive and driven shafts for scoring or wear. Replace with new shafts if necessary. The driven shaft
is serviced as a gear and shaft assembly only.
The mating faces of the pump body and cover must be flat and smooth and fit tightly together. Any scratches
or slight damage may result in pressure leaks. Also check for wear at areas contacted by gears and shafts.
Replace the cover or body if necessary.
The relief valve must be free from score marks and burrs and fit its seat in the pump body. If the relief valve is
scored and cannot be cleaned up with fine emery cloth or crocus cloth, it must be replaced.
Assemble Fuel Pump
1. Lubricate the lips of the oil seals with a light coat of vegetable shortening, then install the oil seals in the
pump body as follows:
a. Place the inner oil seal on the pilot of the installer handle J 1508-8 so that the lip of the seal will face
toward the shoulder on the tool.
b. With the pump body supported on wood blocks, insert the oil seal and tool in the pump body and
drive the seal in until it bottoms in the counterbore ( Fig. 6).
c. Place the shorter end of the adaptor J 1508-9 over the pilot and against the shoulder of the installer
handle. Place the outer oil seal on the pilot of the installer handle with the lip of the seal facing the
adaptor. Then, insert the pilot of the installer handle into the pump body and drive the seal in ( Fig.
7) until the shoulder of the adaptor contacts the pump body. Thus the oil seals will be positioned so
that the space between them will correspond with the drain holes located in the bottom of the pump
body.
2. Clamp the pump body in a bench vise (equipped with soft jaws) with the valve cavity up. Lubricate the
outside diameter of the valve and place it in the cavity
December, 1970 SEC. 2.2
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