Piper Cherokee LANCE, Service Manual

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PIPER CHEROKEE SIX / LANCE SERVICE MANUAL
07/15/06 VA - HYDRAULIC SYSTEM
1J5
3. Raise the head assembly (l) off the armature (8) and note the small thrust ball (7) located
between the end of the armature (8) and motor head. Do not misplace this bearing.
4. Draw the armature from the motor frame (9). Note the number of thrust washers (11) mounted
on the drive end of the armature shaft.
5. Remove the motor frame from the pump reservoir (13).
c. Valve and Gear Case: Remove valve and gear case (15) from reservoir (13) as follows:
1. Remove eight screws from flange of body and separate the two assemblies (18).
2. Pump gears and valves should be removed for cleaning purposes only. To remove cap securing
gears, remove attaching bolts. The two valve springs should be positively identified with their
cavities; otherwise, it will be necessary to readjust each valve for proper operating pressure.
5A-7. CLEANING, INSPECTION AND REPAIRS OF HYDRAULIC PUMP.
NOTE: Repair facilities must be clean to prevent contamination of pump components. Proper and
careful handling should be exercised to prevent damaging pump components.
a. Discard all O-rings.
b. Remove caps or plugs and clean all components with a dry type cleaning solvent and dry
thoroughly.
c. Inspect pump components for scratches, scores, chips, cracks and wear.
d. Inspect motor for worn brushes (minimum of .218 brush remains between the braided wire and
commutator end), excess wear and excess bearing wear.
NOTE: Replacement brushes for original equipment Prestolite pumps are no longer available.
When existing brushes wear out, install a new service replacement Oildyne pump
P/N 38998-004. Order as pump assembly P/N 38992-804 along with a new pump cover
P/N 764-785.
e. Repairs are limited to brush replacement as follows:
1. One brush holder has the winding wire attached. Locate this wire and remove by using a
soldering gun.
2. The head assembly can now be removed and worked on for ease of brush replacement if
required.
3. Remove brush wire and brush from by-metal heat protector.
4. Solder new brush wires to head assembly and by-metal heat protector, and wire from winding
to one brush holder.
5. Install brush springs and brushes into brush holders and secure in place (temporary) with a
piece of string looped around the brush and holder and tied in a knot.
NOTE: Ensure that the braided wire is in the holder slot for proper brush movement.
6. Install the head assembly with new brushes to the frame and commutator in accordance with
instructions given in Paragraph 5A-8, Step a.