Figure 4-54. Coolant Temperature Transmitter
increases. If the transmitter is functioning
properly, the resistance should read 143
±14 5 ohms at 120°G (49°C).
(4) The transmitter is not repairable. If it does
not indicate a resistance within the above
range, it should be replaced.
(1) Screw temperature transmitter into water
(2) Connect wire with washers and nut.
(3) Plug drain and close draincock.
(4) Fill radiator with coolant in accordance with
4-82. TEMPERATURE SWITCH. (See figure 4-40.)
temperature. When coolant exceeds 217 ± 3°F (103 ±
2°C), the normally closed contacts open and the
normally open contacts close. This action results in
automatic shutdown of engine operation at coolant
temperatures exceeding 217 ± 3°F (103 ± 2°C).
Inspection. Inspect switch for corrosion and
connector is secure. The switch is not
repairable and replacement is necessary when it
fails to operate. If the engine is not overheating
and the units shuts down as though it were, or if
the engine continues to operate when running
hot, the switch should be removed and tested as
a possible cause of trouble.
Removal. (See figure 4-55.) Loosen connector,
pull wiring plug, and unscrew temperature
switch from water manifold.
(1) Connect ohmmeter set to Rx1 scale across
(2) Suspend switch in a container of antifreeze.
Switch should be inserted so that sensing
connector end is out of antifreeze.
(3) Heat antifreeze gradually and stir so heat is
(4) Check temperature of antifreeze with a
(5) When antifreeze has reached 214°F (90°
C), the switch should open and the
ohmmeter should read less than 1 ohm.
(6) Allow antifreeze to cool. As the temperature
drops to below 212°F (89°C) the switch
should close and the ohmmeter should read
(7) The switch is not repairable. If it does not
operate within the above limits it should be
VIBRATION DAMPER AND CRACKSHAFT
PULLEY. (See figure 4-40.) The vibration
damper and crankshaft pulley are mounted on
the front end of the crankshaft. Inspect as