Piper Navajo PA-31 Service Manual page 950

PIPER NAVAJO SERVICE MANUAL
9. Insert the fitting on end of nozzle fuel tube through the opening in jacket (5) and attach the
nozzle holder to the combustion head assembly (6) with the two screws. It may be necessary to place a
slight bend in the shrouded fuel tube to permit alignment of screw holes. Be sure to use new gasket (28).
10. Using a new spark plug gasket, install the spark plug (32) and tighten to a torque of 28
foot-pounds. Install the grommet (39) in the jacket around the spark plug.
11. Install the ignition assembly (2) on the jacket assembly (5) with the four attaching screws.
Connect the high-voltage lead to the spark plug and tighten it to 20 foot-pounds.
12. Attach the overheat limit switch (25) and two spacer gaskets (27) to the jacket assembly (5)
with attachment screws. Tighten the screws securely.
13. Attach the cycling switch (24) to the jacket assembly (5) with the two screws.
NOTE
After installing the overheat limit switch and cycling switch,
visually check to make sure that the switch does not come in
contact with combustion chamber. If necessary, add an additional
shim.
14. Place the terminal strip insulation (36) in position on the jacket (5), followed by the
terminal strip (35). Secure both parts by installing attachment screws.
15. Center the fuel fitting in jacket opening. Place the fuel shroud (9), gasket (29), washer (41)
on the fuel fitting and install the nut (38) finger tight. Insert a 3/4 inch open-end wrench inside the jacket
and hold the fuel tube fitting while tightening the nut (38) with a 3/4 inch deep socket. Install the elbow
fitting (34) and the solenoid (22) carefully route solenoid lead wires through hole in shroud and install
grommet.
16. Rotate the combustion air switch (26) onto the threaded fitting on the combustion air tube
and tighten firmly.
17. Slide the grommet (45) over the combustion air tube and connect the tube to the tee fitting
(33) on the combustion air pressure switch (26). If necessary, split the grommet for easier installation.
18. Install the wiring harness and connect all wire leads to their respective terminals. (Refer to
the wiring diagram, Figure 13-12) Place the grommet (45) in position in the jacket (5); locate the
ventilating air blower (11) at the end of the jacket. Thread the quick-disconnect on the motor leads through
the grommet and connect it to the mating connector on the wiring harness.
19. Place the blower housing-in position on the jacket assembly (5) and secure it by installing
the four screws (20), if removed at disassembly. This operation is easier if the screws (20) are started into
their threads and the blower housing rotated into place, allowing the screws to enter the notched openings
in edge of blower housing. Tighten all screws securely.
20. Install the adapter (23) with attaching screw.
Revised: 1/29/82
5C2
HEATING AND VENTILATING SYSEM
5C20