Replace the complete burner as an assembly if the
plate and bushing assembly is defective.
(9) Heat exchanger (fig. 3-10.2).
(a) Inspect the heat exchanger (15) for leaks,
cracks, and carbon deposits. The interior of a unit
which has been burning leaded gasoline will contain
a deposit of lead by-products. Clean the heat ex-
changer as instructed in paragraph 3-34e.
(b) Check for warping of inner passages, or
bulging of the heater plate. Replace the heat ex-
changer if warping or bulging is excessive, or if any
part is burned through.
(c) Small cracks may be repaired by welding,
provided they are accessible and the heat exchanger
is otherwise in good condition. Do not attempt to
repair large cracks, or to straighten a deformed heat
Carefully inspect the heat exchanger, and
repair or replace it if damaged. Exhaust
gases are directed through the heat ex-
changer. These gases contain carbon
monoxide, a colorless, odorless, deadly
poisonous gas. Cracks or holes in the heat
exchanger permit the exhaust gases to en-
ter the heated compartment. This can
result in the serious illness or death of
personnel in the compartment. Never
take chances with a defective heat ex-
(d) When welding cracks in the heat ex-
changer, Type 310 weld rod is preferred, although
Type 349, 321, or 347 may be used. Before welding,
it is very important to clean all combustion deposits
away from the area to be welded, since deposits in
the exchanger can contaminate the weld to such an
extent that a tight weld is almost impossible. Keep
weld beads as small as possible, preferably not over
(10) Miscellaneous heater parts (fig. 3-10.2).
(a) Inspect the guard assembly (16) for
cracks, dents, distortion, loose or defective
fasteners, and other damage; replace a damaged
(b) Inspect the secondary blower housing (3)
for cracks, distortion, loose weldments, and other
damage; replace damaged parts.
(c) Inspect the heater housing assembly (28)
for cracks, dents, distortion, missing weld nuts,
broken studs, broken weldments, and other damage;
replace a damaged housing.
3-36. Reassembly and Installation
a. Reassembly of Air Control Assembly. Refer to
figure 3-10.1 and reassemble the air control assem-
b. Personnel Heater Components.
(1) Fuel control valve reassembly (fig. 3-10.4).
(a) Install the elbow (11) on the valve body
(18), and position it as shown in figure 3-10.8).
(b) If the thermostat (17, fig. 3-10.4) was
removed, position it on the valve body and secure
with two screws (15). Install the wire (14), making
sure the insulator (12) and insulating sleeve (13) are
in place before soldering the wire to the heater and
thermostat terminals. Solder the cable assembly
(16) to the other thermostat terminal.
(c) Install seal (36) on plunger (35) and insert
valve spring (26) in the plunger assembly. Insert
assembled spring and plunger into sleeve and core
assembly (28). Position gasket (27) and sleeve and
core assembly (28) on valve body, and install
solenoid cup (29) with three screws (33) to retain
part. Repeat to install plunger assembly (34) on
(d) Screw valve core (19) in valve body. Install
new preformed packing (25) in recess in valve body.
Install diaphragm assembly (24) and diaphragm cap
(23). Fasten with four screws (20). Insert diaphragm
spring (22) in adjusting screw (21) and install parts
in diaphragm cap.
Do not attempt to replace the valve core
(19) with an automobile tire valve core.
Despite their similarity of appearance, a
tire valve has not been designed for use
with the fuels used in this heater, and will
deteriorate rapidly if installed in the fuel
control valve instead of valve core fur-
nished for the fuel control valve.
(e) Install three small preformed packings (9)
into recesses in valve body. Set restriction orifice
plate (8) and 3-hole plate (7) in place and install
preformed packing (6). Install insulator plate (5) and
outer plate (4) and fasten with three screws (3).
(f) Install washer (30) and coil assembly (31)
in restriction solenoid cup and fasten with screw
(32). Repeat with the coil assembly (10) in the shut-
off solenoid cup. See fig. 3-10.8 for proper orien-
tation of these coils in the valve body.