Cleaning Inspection And Repair Of Emergency Electric Fuel Pump; Assembly Of Emergency Electric Fuel Pump - Piper Navajo Chieftain PA-31-350 Service Manual

NAVAJO CHIEFTAIN SERVICE MANUAL
c. Insert number 540 screws into tapped hole or face of insert (10) and pull insert assembly from
pump body. If necessary, pry the insert loose from the pump body using a lever arm between the pump body
and screw head.
d. Remove rotor (13) from insert by pushing on the end of rotor shaft. Remove blade retaining spring
(12) and blades (11). Also O-ring seals (9).
e. Using a light arbor press, apply pressure to valve adjusting screw (25) to release tension against
the Tru-Arc retaining spring (27) and remove the spring with Tru-Arc pliers. Pull out adjustment guide
(24)
containing O-ring seal (23), adjusting screw (25) and locknut (26).
f. Remove the valve spring (22) and piston assembly (21).
g. Remove the bearing retainer insert (20) from pump body, when required, by means of an arbor
press.
9-52. CLEANING, INSPECTION AND REPAIR OF EMERGENCY ELECTRIC FUEL PUMP
a. Clean all parts in oil solvent such as mineral spirits.
b. Inspect all parts for wear, with special attention to the insert, rotor and blades. (Check wear limits
per Table IX-II.)
c. Repair is limited to replacing parts that are defective or worn.
9-53. ASSEMBLY OF EMERGENCY ELECTRIC FUEL PUMP. (Refer to Figure 9-12.)
a. Replace the bearing insert retainer (20) and press flush with body housing (4).
b. Lubricate O-ring seals with Parker O-Lube or equivalent to facilitate reassembly.
c. Replace the valve spring (22) and piston assembly (21). Check for free movement of plunger.
d. With the piston assembly (21), valve spring (22), adjustment guide (24) and adjustment screw (25)
in place, secure with Tru-Arc retaining spring (27).
e. Install the rotor (13) into the insert (10) and the rotor blades (11) into the slots with the notches
toward the outer edge of the insert. Secure the blades with the blade retaining spring ( 12). Clearance
across
the top of the rotor and blades should measure a nominal 0.0005 after reassembly.
f.
Replace the two O-ring seals (9) on the insert (10).
g. Install the insert and rotor assembly into the pump body (4).
h. Install the O-ring seal (17) on the insert plug (16) and install plug into pump body (4). Newer
pumps with wear plate (14) in plug (16), be sure the wear plate spring (15) is between the wear plate
(14) and
the plug (16), before installing plug into pump body.
i. Replace the seal cage (8), seal washer (6) and seal spring (5) on the rotor shaft before installing the
motor to the pump body.
j.
Replace the motor on the pump body being sure the female end of the motor shaft fits over the
male end of the rotor shaft. Secure the motor with attachment hardware.
k. Replace the cover on the end of the motor housing and secure with two screws.
l.
Adjust pump in accordance with paragraph 9-54.
Revised: 3/31/94
FUEL SYSTEM
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