TM 9-2320-361-34 17-2. ENGINE COOlANT HEATER FLAME DETECTOR SWITCH MAINTENANCE THIS TASK COVERS: a. Removal d. Assembly b. Disassembly e. Installation c. Inspection INITIAL SETUP APPLICABLE MODELS MATERIALS/PARTS All Sleeve (Appendix F, Item 261) TEST EQUIPMENT Multimeter (Appendix B, Item 3) TOOLS General mechanic’s tool kit (Appendix B, Item 1) Tool kit, electrical (Appendix B, Item 2) REFERENCES (TM) TM 9-2320-361-20 TM 9-2320-361-34P EQUIPMENT CONDITION Engine coolant heater removed (TM 9-2320-361-20). NOTE Tag wires for installation. a. Removal 1. Remove four screws (6) and guard (7) from heater housing (8). 2. Remove nut-assembled lockwasher (2), ground lead (3), air tube (4), and elbows (1) and (5) from heater housing (8). 3. Remove five screw-assembled lockwashers (11) and six leads (12) from flame detector switch (10). 4. Loosen nut (9) and remove flame detector switch (10) from heater housing (8). b. Disassembly 1. Remove adjusting screw (15), washer (16), and spring (17) from switch bracket (24) and mount (18). CAUTION Ceramic rod is very brittle and is easily broken; handle carefully. 2. Tilt microswitch (13) back on switch bracket (24), invert, and remove ceramic rod (22) from probe (20). 3. Remove two nut-assembled lockwashers (14), screws (23), and microswitch (13) from switch bracket (24). 4. Remove split roll pin (21) and switch bracket (24) from mount (18). 5. Remove sleeve (19) and nut (9) from probe (20). c. Inspection 1. Inspect flame detector switch (10) for broken ceramic rod (22) or bent probe (20). Replace ceramic rod (22) if broken. Replace flame detector switch (10) if probe (20) is bent. 2. Inspect flame detector switch (10) for carbon buildup and corrosion. Remove carbon buildup or corrosion. 17-2