Defuel The Fuel System; Defuel The Main Fuel Cell At The Gravity Fill Port; Defuel The Main Fuel Cell At The Sump Drain; Defuel The Supplemental Fuel Cell - MD Helicopters MD Explorer Servicing And Maintenance

3. Defuel the Fuel System

NOTE:
The main fuel tank system can be de­
fueled at the gravity filler port or the sump
drain. But the gravity filler port method
cannot completely drain all of the fuel from
the main tank. The sump drain procedure
must be done after the gravity filler port
procedure to completely empty the fuel
tank.
A. Defuel the Main Fuel Cell at the Gravity
Fill Port
Special Tools
(Ref. CSP−SPM)
Item Nomenclature
T804 Fuel Suction Pump Kit
T804−1 Fuel Suction Pump Hose Set
Obey all fuel system servic­
WARNING
ing precautions.
(1). Ground the rotorcraft (ref. Figure 204).
(2). Remove filler cap (2).
NOTE:
There is an optional locking fuel cap
that can be installed on the gravity fill port.
A key is necessary to lock or open the fuel
cap.
(3). Put the lanyard in the slot provided in
the filler cap adapter.
(4). Put 1.375 inch (34.93 mm) fuel suction
pump hose set (T804-1) in the fuel cell
through gravity fill port (1).
Aviation Turbine Fuel
The gravity filler port cannot
CAUTION
completely drain all of the fuel
from the main fuel tank.
(5). Drain the fuel with fuel suction pump
kit (T804) or a fuel service truck with
defueling capabilities.
(a). Drain the fuel into a suitable storage
container.
MD Helicopters, Inc.
Rotorcraft Maintenance Manual
(6). Remove the hose from gravity fill port.
(7). Install filler cap (2).
(8). If the fuel cell is to stay empty for more
B. Defuel the Main Fuel Cell at the Sump
WARNING
NOTE:
on the bottom centered on the sump plate.
The valves are spring-loaded, normally
closed, poppet drain valves. The valves open
by pushing the control cable internal plung­
er attached to fuel drain valve.
(1). Make sure the rotorcraft is as level as
(2). Open access panels B178 and R185 (ref.
(3). Place a suitable container under fuel
(4). Push the buttons of fuel sump drain
(5). Close access panels B178 and R185 (ref.
(6). If the fuel cell is to stay empty for more
C. Defuel the Supplemental Fuel Cell
(1). Apply electrical power to the rotorcraft
(2). Actuate supplemental fuel transfer
(3). Remove electrical power (ref. Section
12-00-00
(b). Drain the remaining fuel at the sump
drain (ref. Procedure 3.B.).
than 5 days, do the fuel cell preserva­
tion procedure (ref. Section 10-10-00).
Drain
Obey all fuel system servic­
ing precautions.
Two fuel sump drain valves are located
possible.
Section 06-00-00).
drain valves.
Aviation Turbine Fuel
controls to drain the fuel.
Section 06-00-00).
than 5 days, do the fuel cell preserva­
tion procedure (ref. Section 10-10-00).
(ref. Section 96-00-00).
pump until the supplemental fuel
gauge indicates EMPTY (ref. Section
96-00-00).
96-00-00).
CSP−900RMM−2
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Revision 34