Engine Description
Teledyne Continental Motors, Inc.
TM
2-2.7.1. Fuel Pump
An engine-driven, positive displacement vane fuel pump supplies fuel as required to the
fuel injectors. Fuel enters the fuel pump at the well of the swirl chamber where the fuel is
centrifuged and the liquid is separated from fuel vapor. The liquid fuel is directed to the
fuel pump blades. The fuel pump blades force the fuel to the fuel pump outlet through
various fittings and fuel lines through the 32-micron fuel filter. The 32-micron, in-line
type fuel filter is situated between the engine-driven fuel pump and the fuel distribution
block. From the fuel filter, fuel flows to the fuel distribution block, where a screen filters
particulates larger than 10 microns, and subsequently to the injector nozzles.
The fuel pump is directly driven at the same speed as the crankshaft. Therefore, fuel flow
and fuel pressure vary directly with engine speed. An adjustable relief valve maintains
pump flow and pressure for the lower engine speeds, while an adjustable orifice controls
fuel pump pressure for the higher engine speeds. This combination of mechanical control
circuits ensures proper pump pressure and delivery for all engine operating speeds.
A check valve on the fuel pump permits the use of an aircraft auxiliary electric fuel boost
pump during engine priming and starting (to allow the aircraft boost pump to bypass the
engine driven fuel pump) or in the unlikely event of an engine driven fuel pump
malfunction.
INLET FROM FUEL TANK
VAPOR SEPARATOR
BODY
PUMP ASSEMBLY
BY-PASS CHECK VALVE
RELIEF
VALVE
DRY BAY DRAIN
VAPOR SEPARATOR
VAPOR
RETURN
VAPOR
RETURN
ADJUSTABLE
ORIFICE
FUEL PUMP
OUTLET
Figure 2-14.
Fuel Pump
2-16
IOF-240 Series Engine Maintenance Manual
Change 1
31 August 2007