TM-9-2320-361-24-2 Field Maintenance Manual Volume 2 for M44A2 Series Trucks
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TM 9-2320-361-24-2 0417 00 0417 00-2 ENGINE COOLANT HEATER FLAME DETECTOR SWITCH MAINTENANCE (Contd) NOTE Prior to removal, tag lead wires for installation. 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). Discard nut-assembled lockwasher (2). 3. Remove five screw-assembled lockwashers (11) and six leads (12) from flame detector switch (10). Discard screw-assembled lockwashers (11). 4. Loosen nut (9) and remove flame detector switch (10) from heater housing (8). 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). Discard nut-assembled lockwashers (14). 4. Remove split roll pin (21) and switch bracket (24) from mount (18). 5. Remove sleeve (19) and nut (9) from probe (20). Discard sleeve (19). 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. Refer to WP 0021 00 for general inspection procedures.