TM 9-2320-260-34-2
17-3. ENGINE COOLANT HEATER FLAME DETECTOR SWITCH MAINTENANCE
THIS TASK COVERS:
a. Removal
d. Assembly
e. Installation
b. Disassembly
c. Inspection
INITIAL SETUP
MATERIALS/PARTS (Contd)
APPLICABLE MODELS
Four screw-assembled Iockwashers
All
TEST EQUIPMENT
Sleeve (Appendix D, Item 509)
Multimeter (Appendix B, Item 115)
Insulation varnish (Appendix C, Item 17)
TOOLS
REFERENCES (TM)
General mechanic's tool kit
TM 9-2320-260-20
(Appendix B, Item 1)
TM 9-2320-260-34P-2
Tool kit, electrical (Appendix B, Item 106)
EQUIPMENT CONDITION
MATERIALS/PARTS
Engine coolant heater removed (TM 9-2320-260-20).
Five screw-assembled lockwashers
NOTE
Tag wires for installation.
a .Removal
1. Remove four screw-assembled lockwashers (9) and guard (10) from heater housing (11). Discard
screw-assembled lockwashers (9).
2. Remove nut-assembled lockwasher (2), ground lead (3), air tube (4), and elbows (1) and (5) from
heater housing (11).
3. Remove five screw-assembled lockwashers (12) and six leads (6) from flame detector switch (7).
Discard screw-assembled lockwashers (12).
4. Loosen nut (8) and remove flame detector switch (7) from heater housing (11).
b. Disassembly
1. Remove adjusting screw (15), washer (14), and spring (20) from microswitch (16) and mount (19).
CAUTION
Ceramic rod is very brittle and is easily broken; handle carefully.
2. Tilt microswitch (16) back on mount (19), invert, and remove ceramic rod (13) from probe (17).
3. Remove sleeve (18) and nut (8) from probe (17). Discard sleeve (18).
c. Inspection
1. Inspect probe (17) of flange detector switch (7) for bends and corrosion. Remove corrosion from
probe (17). Replace flame detector switch (7) if bent.
2. Inspect ceramic rod (13) for chips, cracks, and breaks. Replace ceramic rod (13) if chipped, cracked,
or broken.
17-4
