Maintenance Practices; Description And Operation - MD Helicopters MD900 Instructions Manual

1. Description and Operation

(Ref. Figure 201)
The airframe fuel filter is a 10 micron, 500
square inch disposable filter element that
strips the fuel of solid contaminates prior to
entering the engine fuel system.
The left and right airframe fuel filters are
installed in the baggage compartment.
The airframe fuel filter is mounted in series
between the aircraft fuel system and the
engine fuel system.
A differential pressure sensing switch is
contained in the airframe fuel filter. When the
switch in the filter body detects an increase in
MD Helicopters Inc.
Optional Equipment Manual
900P5663200
AIRFRAME FUEL FILTER

MAINTENANCE PRACTICES

the filter differential pressure due to partial or
complete filter blockage, the switch may
intermittently or completely close. Switch
contacts complete an electrical circuit that
turns on the FUEL FILTER L or R caution
light on the instrument panel. When the filter
becomes fully clogged, a by−pass valve
contained in the airframe fuel filter opens and
the fuel bypasses the filter element.
A press−to−test button is located on top of the
filter body. Pressing the button will illuminate
the FUEL FILTER L or R caution light on
the instrument panel.
A filter bowl drain valve plumbed into the
drain manifold provides for filter draining and
fuel sampling.
CSP–900–S4
Airframe Fuel Filter
Page 201
Original