Piper Navajo Chieftain PA-31-350 Service Manual page 809

NAVAJO CHIEFTAIN SERVICE MANUAL
f. Place a new rope gasket (21) in position on the exhaust outlet. Spring the jacket assembly (1)
open at the seam and insert the combustion tube assembly (20) carefully into the jacket. Exercise care to
clear the pressure switch tube in the exhaust outlet and see that the rope gasket (21) is properly located.
Close the gap on the jacket assembly and install screws to secure it at the seam. (Solenoid lead wire is
grounded under one of these screws. See notations made during disassembly.) Make sure the seam is in good
condition and a tight fit is effected.
g.
Install cable straps at locations noted during disassembly.
h. If new spray nozzle is not being installed, remove the original nozzle (23) from the polyethylene
bag. Screw the nozzle into nozzle holder and tighten to 75-100 inch-pounds. It is very important to torque
the nozzle to this value, as incorrect tightening could cause improper heater operation and "drool."
CAUTION
The spray nozzle has a slight protrusion on the nozzle face. If this
area has been struck by any object which would make a dent or
destroy the original contour, the nozzle must be replaced.
i. Install a new head gasket (49) and the head assembly (37) to the combustion tube assembly (20)
with six screws.
NOTE
When installing combustion head, do not tighten six mounting
screws until spark plug is installed. This will insure the proper
alignment of spark plug with combustion head. Tighten six screws
after plug is installed.
j. Insert the fitting on end of nozzle fuel tube through the opening in jacket (1) and attach the
nozzle holder to the combustion head assembly (37) 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 a new gasket (24).
k. Using a new spark plug gasket, install the spark plug (6) and tighten to a torque of 28
foot-pounds. Install the grommet (12) in the jacket around the spark plug.
1. Install the ignition assembly (4) on the jacket assembly (1) with the four screws. Connect the
high voltage lead to the spark plug and tighten it to 20 foot-pounds.
m. Attach the overhead limit switch (8) and two spacer gaskets to the jacket assembly (1) with two
screws. Tighten the screws securely.
n. Attach the cycling switch ( 11) to the jacket assembly (1) with the two screws.
o. Place the terminal strip insulation (9) in position on the jacket (1) followed by the terminal strip
(10). Secure both parts by installing the two screws.
p. Center the fuel fitting in jacket opening. Place the fuel fitting shroud gasket (42), washer (50)
and shroud (45) on the fuel fitting, and install the nut (48) finger tight. Insert a 3/4 inch open-end wrench
inside the jacket and hold the fuel-tube fitting while tightening the nut (48) with a 3/4 inch deep socket.
Install the elbow fitting (44) and solenoid (47). Carefully pull solenoid lead wires through hole in shroud
and install grommet (38).
Reissued: 9/23/80
HEATING AND VENTILATING SYSTEM
4C17