TM 9-6115-604-34
NAVFAC P-8-633-34
Figure 12-4. Oil Pressure Alarm and Shutdown Switch OP1/OP2 Test Setup
12-13. COOLANT LEVEL SWITCH S13/S14.
a.
General. Two identical sensors, located at different levels in the radiator top tank are used to detect
coolant loss. The upper sensor activates the annunciator system, and the lower sensor trips the engine
shutdown system.
b.
Apparatus. A clean, 20 gallon (76 L) container to catch the drained coolant.
c.
Procedure.
(1)
Preparation.
(a)
Check that the coolant is at the proper level in the radiator. If necessary, add coolant to bring
the level to approximately 2.5 inches (63.5 mm) from the top of the filler neck
(b)
Operate the set at rated speed and no load until normal operating temperature is reached.
(2)
Test.
CAUTION
To avoid overheating the engine during the following tests, do not drain more than 20 gallons (76 L)
of coolant from the radiator. If the coolant level protection system falls to activate at this point,
discontinue the test and repair the system as necessary.
(a)
Open the coolant drain valve until the annunciator system activates, and dose the drain valve.
(b)
Measure and record the distance from the top of the filler neck to the coolant level in the tank
(c)
Reopen the drain valve until the engine shuts down, and dose the valve.
(d)
Measure and record the distance from the top of the filler neck to the coolant level in the tank
(e)
Return the drained coolant to the radiator.
(3)
Results.
(a)
The annunciator system shall activate at a coolant level of 5.2 to 5.5 inches (132 to 140 mm)
measured from the top of the filler neck
(b)
Engine shutdown shall occur at a coolant level of 7.0 to 7.3 inches (178 to 185 mm) measured from
the top of the filler neck
(c)
If either system failed to activate, or activated at the wrong coolant level, troubleshoot the system in
accordance with Chapter 2.
12-18
