ENGINE COOLANT HEATER REPAIR.
This task covers:
b. Cleaning and Inspection
d, Flame Switch Adjustment
l Engine coolant heater removed.
(See TM 9-2320-289-20)
l Soldering gun
Two O rings
Lead solder (Item 62, Appendix B)
Antiseize tape (Item 65, Appendix B)
(Item 71-, Appendix B)
Ensure that all terminals and leads are tagged for assembly.
Turn spring loaded screws securing cover 1/4 turn and remove cover.
Remove 4 screws (5) securing electrical receptacle (11) to bracket. Remove screws and leads
at terminal block (6).
Disconnect all leads at relay assembly (17), Unsolder pink/black lead at relay assembly.
Remove clamp (13), mounting bracket, 2 screws, and relay assembly.
Disconnect leads at timer (1 5), Remove nut, bolt (14), Iockwasher, timer, backing plate, and
receptacle assembly (11), Discard Iockwasher,
Remove remaining screw and terminal block (6) from case.
Disconnect leads from flame switch (7). Loosen nut on bottom of flame switch and pull flame
switch straight up to remove.
Loosen 2 clamps (3) and remove fuel hose (4).
Disconnect leads from limit switch (8). Remove 2 screws and limit switch.
Remove screw from thermostat valve bracket and remove thermostat valve (18). Remove 4
screws, fuel control bracket (2), and fuel control (1). Remove screw and remove fuel control
from bracket if damaged,
Disconnect lead from igniter (16), Remove igniter and gasket, Discard gasket. Remove water
coolant fittings (9) if damaged and discard.
Remove 8 screws and air inlet cover (20) from case.
Remove 4 screws (22) securing 2 halves of case together.