Engine Fuel Injection; Engine Air Induction System; Engine Fuel Ignition - Cirrus DESIGN SR20 Information Manual

Section 7 Cirrus Design
Airplane Description SR20
the engine compartment through two vents in the aft portion of the
cowling. No movable cowl flaps are used.

Engine Fuel Injection

The multi-nozzle, continuous-flow fuel injection system supplies fuel
for engine operation. An engine driven fuel pump draws fuel from the
selected wing tank and passes it to the mixture control valve integral to
the pump. The mixture control valve proportions fuel in response to the
pilot operated mixture control lever position and automatically provides
altitude compensation to supply the proper full rich mixture at any
altitude. From the mixture control, fuel is routed to the fuel-metering
valve on the air-induction system throttle body. The fuel-metering valve
adjusts fuel flow in response to the pilot controlled Power Lever
position. From the metering valve, fuel is directed to the fuel manifold
valve (spider) and then to the individual injector nozzles. The system
meters fuel flow in proportion to engine RPM, throttle angle, and
ambient altitude pressure. Manual mixture control and idle cut-off are
provided. An electric fuel pump provides fuel boost for vapor
suppression and for priming.

Engine Air Induction System

Induction air enters the engine compartment through the two inlets in
the forward cowling. The air passes through a dry-foam induction filter,
through the throttle butterfly, into the six-tube engine manifold, and
finally through the cylinder intake ports into the combustion chambers.
Should the dry induction filter become clogged, a pilot controlled
alternate induction air door can be opened, allowing engine operation
to continue. Refer to Engine Controls, Alternate Air Control.

Engine Fuel Ignition

Two engine-driven magnetos and two spark plugs in each cylinder
provide fuel ignition. The right magneto fires the lower right and upper
left spark plugs, and the left magneto fires the lower left and upper
right spark plugs. Normal operation is conducted with both magnetos,
as more complete burning of the fuel-air mixture occurs with dual
ignition.
7-34 P/N 13999-002 Info Manual
September 2011