Piper COMANCHE PA-24-180 Service Manual page 513

PIPER COMANCHE SERVICE MANUAL
b. Inspect the coupling (2). Use a new coupling if the old one appeanrs deteriorated.
c. Rearoemble the pump with a new motor guket (11) and a new motor if required. Tighten the
motor nuts (14) just snug. Be sure the coupling (2) engages both the pump shaft and the motor shaft.
d. Run the pump at free delivery with test fluid. Use an ammeter to measure motor current. Tap
motor to position it so that current is a minimum. Tighten motor nuts to approximately 15 in. lbs. Test
pump u described in pargraph 5: the 24-hour run-in may be omitted.
4. Shaft Sal Replacement.
a. Remove motor and associated pares u descibed in Section 3. Remove cover and associated
parts u described in pangnph 2. Remove the eight vanes (6) with cae to avoid damagin them.
b. If a retaining ring is found on the pump shaft, remove this with suitable pliers and discard the
ring. Push the rotor assembly out of the pump. Remove the housing insert (4), noing its position. Using a
.40 to .41 diameter, flat faced brss drift and arbor pre, press the shaft seal (12) out of the housing (3).
Use care to avoid damaging the bearing surfaces. Parts may now be washed in a mild solvent.
c. Apply a thin uniform coating of "John Crane Plasuc Lead Seal No. 2" to the outside diameter
of a new shaft seal (12). (This seal may be a different type than the one which was in the pump.) With the
cover end of the housing assembly on a
,' surface, use a 15/16 diameter flat faced brass drift in an arbor
press to press the shaft sel (12) home in .he housing asembly (3).
d. Place the insertion tool (Figure 8-17) over the end of the rotor asembly (5). Use motor oil
to lubncate the end of the insertion tool and the shaft seal. Push and twst the rotor assembly into the
housing assembly. Insall the housing insert (4). Install the vanes (6) radius end away from center. Install
the cover and associated parts per paragraph 2. Remove insetion tool. then install the motor and associated
prrs per Section 3. Run n and test as described in paragraph 5.
5. Performance Requirements For Motor Drven Fuel Pumps.
a. General.
1. Test fuel to be odorless mineral spirits, specific gravity 76, viscostv 1.0 cs @ 78 F.
2. Pump shall be mounted with the motor horizontal.
flow.
4. 14 volts D.C. of the proper polarity shall be used throughout.
b. Requirements.
1. Pump to be run for 24 hours a 14 volts vith restncted outlet.
2. Run pump unnl all air is removed from the system.
3. Restrict fuel flow completelv.
Model No.
Presure
Flow Amperes
480 518-1 or 480 528
15 psi
45 gph min. 5 5 max.
480 533
20 psi
85 gph mm. 7.5 max.
4. Check for leakage at seal, cover gasket and through casings.
5. Restrict flow as follows:
Model No. Shutoff Pressure Amperes
480 518-1 or 480 528
25 psi max. 6 5 max.
480 533 40 psi max.
10. max.
6. Observe for undue noise dunng all phases of calibraion. Excessive noise shall be cause for
rejecnon.
FUEL SYSTEM
ISSUED: 8/18/72
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