Figure 4. Removing Oil Seals
Observe the position of the oil seal lips before removing the old seals to permit installation of the new
seals in the same position.
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.
Check the pump gear teeth for scoring, chipping, or wear. Check the ball slot in the drive gear for wear. If
necessary, replace the gear.
Inspect the drive and driven shafts for scoring or wear. Replace the 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 the gears and
shafts. Replace the pump 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 valve is
scored and cannot be cleaned up with fine emery cloth or crocus cloth, it must be replaced.
Current standard fuel pumps (with 1/4-inch-wide gears) incorporate a 1/8 inch shorter pump body with three
drain holes, a 1/8 inch shorter drive shaft and a cover with a 3/8 inch inlet opening. When replacing a former
pump, a 3/8 x 1/4 inch reducing bushing is required for the inlet opening and the unused drain holes must be
Assemble Fuel Pump
Refer to Fig. 1, 2, and 5 and assemble the pump as follows:
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 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 woodblocks (Fig. 6), insert the pilot of the installer handle in the pump
body so the seal starts straight into the pump flange. Then drive the seal in until it bottoms.
c. Place the shorter end of adaptor J 1508-9 over the pilot and against the shoulder of the installer handle.