TM 10-4330-237-13&P
Section III. PRINCIPLES OF OPERATION
1.11 GENERAL FUNCTIONAL DESCRIPTION. (Refer to figure 1-2.)
The liquid fuel filter-separator houses a horizontal filter vessel (1) containing three coalescer elements (2) to remove
particles from the pumpage and coalesce entrained water, and a separator (3) to remove the water drops from the
pumpage. The coalescer elements (2) are arranged in the lower portion of the filter vessel (1) and the separator (3) is
placed in the upper portion. The coalescer elements (2) are mounted to an inlet bulkhead (7) which creates an inlet
chamber in the inlet/outlet (6 and 16) end of the filter vessel (1). The outlet port (16) passes completely through the
chamber. Incoming pumpage impacts a diverter plate (5) which prevents the pumpage from forcefully impacting the lower
coalescer elements and equalizes the pressure in the chamber. Pumpage flows from the inlet chamber to the inside of
the coalescer elements (2) and through the elements into the filter vessel (1). As the pumpage passes through the
coalescer elements (2) particles of matter are trapped in the element and droplets of water are coalesced (grouped and
formed) into larger drops. As the pumpage is forced up towards the separator (3), the force of gravity causes more
particles to fall down to the sump (4). At the separator (3), the Teflon coated screen allows the fuel to pass but repels the
relatively large water drops, which fall into the sump (4). The fuel flows from the outside to the inside of the separator (3)
and out the filter vessel (1) outlet port (16).
Figure 1-2. Liquid Fuel Filter-Separator Component Location
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