(8) Install connecting red assembly (para
4-2b(1) through (8)).
(9) Install tubing coupling, and pin (para
(12) Install pump assembly
Section Il. M43 DETECTOR UNIT CHASSIS ASSEMBLY (1A2A2)
(4) Pull thermal resistor (3) from cell block
assembly (1) through the cavity top port (5).
General support maintenance personnel are au-
thorized to replace heater circuit resistors, the
(5) Remove remaining insulating compound
from resistor mounting cavity using a No. 4 0
thermal resistor, thermostatic switches, the cell
block assembly, the air inlet heater module,
(or 3/32-inch) drill. Insert drill and rotate manu-
shaft assembly, switch assembly, and the branch-
ed wiring harness.
(1) Install the thermal resistor (3), lead-
Use minimum heat and force when un-
end first, into the cavity top port (5). Adjust
thermal resistor (3) downward in cavity until
terminals. If a terminal is dislodged,
leads are about halfway through.
( 2 ) Apply insulating compound (item 1,
it back into its mounting hole, and al-
table 11) into top port
of the resistor cavity.
low it to cool.
Fill cavity with insulating compound while ad-
justing thermal resistor (3) downward.
Resistors and Terminals
( 3 ) Adjust thermal resistor (3) down-
ward in cavity until sensor tip (2) is directly
over air flow port (4) in the cell block assembly
(1) and about 1/32-inch below the plastic top sur-
face of the cell block assembly.
(4) Carefully seal thermal resistor cavity
(3) Unsolder and remove defective resistor.
top port (5) with insulating compound (item 1,
(4) Unscrew defective terminal stud (55A,
or drill out defective terminal stud
room temperature for 24 hours.
(5) Dress leads of thermal resistor to pro-
per length and solder to terminals (6).
(6) Coat soldered terminals and bare leads
(1) Replace defective terminal studs (55A
w i t h sealant from coating kit (item 6, table
(2) Attach and solder resistor to its ter-
(7) Install chassis assembly to case top as-
(4) Coat soldered joints with sealant from
(3) Remove thermostat retaining bar (6),
washer (7), and lockwasher (8).
(4) Unsolder wires from thermostatic
(2) Remove sealing compound from termi-
switch (9 or 10) terminals.
( 3 ) Unsolder thermal resistor (3) leads
from cell block assembly (1) terminals (6).