TM 5-3810-300-24 & P2
remove any water or sediment. Install new filter elements every 300 hours of operation or more often if plugging is
indicated. A plugged filter can be detected by observing the fuel pressure at the cylinder head fuel inlet manifold and the
inlet restriction at the fuel pump. In a clean system, the maximum pump inlet restriction should not exceed 6 inches of
mercury. At normal operating speeds (1600-2100 rpm) the fuel pressure is 45-70 psi. Change the fuel filter elements
whenever the inlet restriction (suction) at the fuel pump reaches 12 inches of mercury at normal operating speeds (1600-
2100) and whenever the fuel pressure at the inlet manifold falls to 45 psi.
1.
With the engine shut down, place a container under the strainer or filter and open the draincock. Loosen the cover
nut or bolt just enough to allow the fuel oil to drain out freely.
CAUTION
THE WIRING HARNESS, STARTING MOTOR, OR OTHER ELECTRICAL EQUIPMENT SHOULD BE
COVERED DURING THE FILTER CHANGE, SINCE FUEL OIL CAN DAMAGE THE ELECTRICAL
INSULATION.
2.
While supporting the shell, unscrew the cover nut or bolt and remove the shell and the element.
3.
Remove and discard the element, the shell gasket, the cover nut or bolt gasket.
CAUTION
ONLY FILTER ELEMENTS DESIGNED FOR FUEL OIL FILTRATION SHOULD BE USED TO FILTER
THE FUEL.
4.
Wash the shell thoroughly with fuel oil and dry it with compressed air.
5.
Examine the element seat and the retaining ring to make sure they have not slipped out of place. Check the spring
by pressing on the element seat. When released, the seat must return against the retaining ring.
NOTE
THE ELEMENT SEAT, SPRING, WASHER AND SEAL CANNOT BE REOMVED FROM THE
STRAINER SHELL. IF NECESSARY, THE ASSEMBLY MUST BE REPLACED. HOWEVER, THE
COMPONENTS OF THE FILTER SHELL ARE SERVICED. EXAMINE THE FILTER RETAINER SEAL
FOR HARDENING OR CRACKING. IF NECESSARY, REPLACE THE SEAL.
6.
Place a new element over the stud and down against the seat. Make sure the draincock is closed; then, fill the shell
about two-thirds full with clean fuel oil.
NOTE
THOROUGHLY SOAK THE DENSITY-TYPE STRAINER ELEMENT IN CLEAN FUEL OIL BEFORE
INSTALLING IT. THIS WILL EXPEL ANY AIR ENTRAPPED ELEMENT AND IS CONDUCIVE TO A
FASTER START.
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