Europa Aircraft Rotax 914, Installation Manual

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Fuel system check
The next items to check are the electric fuel pumps; this operation can be carried out with the engine
stopped. Disconnect the fuel return line at the fuel pressure regulator, and connect a temporary 8mm
hose from the return line fitting on the regulator leading to a suitable measuring container of at least 1
litre (1 quart) capacity.
Fuel flow check
Disconnect the small bore hose from the control diaphragm at the front of the regulator. Connect the
syringe pump with integral pressure gauge to the regulator, and pressurise the line to 0.35 - 0.4 bar
(5.1 - 5.8 psi).
With the aircraft fuel selector valve on Main, switch on one electric pump, adjusting the pressure into
the regulator to remain in the range of between 0.35 - 0.4 bar (5.1 - 5.8 psi) and measure the flow rate
into the measuring container. It must be at least 125% of the full power fuel consumption. To
achieve this the pump must deliver 1 litre in not more than 87 seconds (1 US quart in 82 seconds).
Do the same check with the other pump and finally with both pumps. Repeat these checks with the
fuel selector on Reserve and record the fuel flows that were achieved.
Note: Quantity pumped (litres) / time (seconds) x 3600 = litres / hour. If using quarts, use the same
formula but don’t forget to divide the result by 4 to obtain gallons / hour
If you cannot achieve sufficient fuel flow, there must be a restriction in the lines between the fuel
outlets and the engine; perhaps a kinked or squashed fuel line.
Now reconnect the fuel tank return line to the regulator , and the pressure line from the airbox to the
regulator control diaphragm.
Fuel pressure check
Connect the pressure gauge via a ‘T’ piece at the fuel inlet and switch on both pumps. Check that the
pressure does not exceed 0.35 bar (5.1 psi). If the fuel pressure does exceed this limit there may be
several reasons. For example, the pressure regulator may be incorrectly adjusted, it may be faulty or
there could be a restriction in the return line.
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Europa XS Rotax 914 Engine Manual Issue 7 June 2004