C
IRRUS
D
ESIGN
S
ECTION
7: A
IRPLANE
AND
S
YSTEMS
SR20
E
NGINE
P/N 11934-005
7-37
key switch, located on the instrument panel, controls ignition and starter
operation. The switch is labeled OFF-R-LBOTH-START. In the OFF posi-
tion, the starter is electrically isolated, the magnetos are grounded and will
not operate. The R and L positions are used for individual magneto checks
and for single magneto operation when required.
The ignition and starter system includes SlickSTART™, which changes the
ignition timing and adds energy to the spark to aid in starting. When the
battery master switch is ON, rotating the switch to the spring loaded
START position energizes the starter and SlickSTART™, and activates both
magnetos. The switch automatically returns to the BOTH position when
released, and SlickSTART™ is deactivated.
28 VDC for Starter operation is supplied through the 2-amp STARTER
circuit breaker on NON-ESSENTIAL BUS.
Air Induction System
Induction air enters the engine compartment through the two inlets in the
forward cowling. The air passes through a paper induction filter, through
the throttle butterfly, into the four-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 induc-
tion air door can be opened, allowing engine operation to continue. For
additional information on the Alternate Air Control, refer to Engine
Controls -
description in this section.
Engine Exhaust
Engine exhaust gases are routed through an exhaust system. After leaving
the cylinders, exhaust gases are routed through the exhaust manifold to a
single muffler located on the left side of the engine compartment, then
overboard through exhaust pipes exiting through the lower cowling. A
muff type heat exchanger, located around the muffler, provides cabin heat.
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 fuel servo, where fuel is proportioned in
response to the pilot-operated mixture control lever position. The fuel
servo adjusts fuel flow in response to the pilot-controlled Power Lever posi-
tion. From the fuel servo, fuel is directed to the fuel injector manifold and
then to the individual injector nozzles. The system meters fuel flow in
proportion to engine RPM, mixture setting, and throttle angle. Manual
mixture control and idle cut-off are provided. An electric fuel pump
provides fuel pressure boost when needed.
Reissue A
