Electronic Fuel Injection (Efi - Westerbeke SBEG Series Operator's Manual

ELECTRONIC FUEL INJECTION (EFI)
SCHRADER VALVE
TO DISTRIBUTOR
STEPPER MOTOR _ _
MAP SENSOR
PRESSURE REGULATOR
THROTTLE BODY
AIR HEATER
PCV VALVE
AIR SCREEN/
FLAME ARRESTOR
;:;~:::::=
NOTE: FAILURE TO KEEP
CLEANJ,i~~~fi~
I
WILL RESULT IN A HIGH INTAKE
"" . .
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DRAW ENGINE LUBE OIL INTO THE BE CONSUMED
BY THE ENGINE THROUGH THE PVC CRANKCASE VENTING VALVE.
CLEAN THIS SCREEN ON A REGULAR BASIS.
COOLANT FEED
DESCRIPTION
The above illustration shows the throttle body assembly
attached to the intake manifold.
An
electronic control unit (BCD) controls the fuel injection
and throttle actuator.
The ECU is supplied with electrical signals it interprets as
engine operating conditions from sensors that monitor intake
air temperature, engine coolant temperature, map sensor
(intake manifold absolute pressure), engine rpm, battery
voltage and distributor cam signal.
The
ECU
interprets this information to detennine the
appropriate injector pulse rate and throttle opening position.
A high pressure fuel pump supplies fuel to the area around
the injector and regulator maintains the fuel pressure in that
area at 35 - 40 PSI.
COOLANT RETURN
The injector is a solenoid operated pintle valve that meters
fuel into the intake manifold depending on engine operating
conditions and generator amperage load as detennined by the
ECU.
Air flow into the intake manifold is controlled by the ECU
operation of the throttle plate via the actuator. Throttle plate
positioning for proper air flow into the engine is
accomplished through the ECU interpretation of engine
operating conditions. The Schrader valve is used to
monitor/check fuel pressure around the fuel injector.
""" WESTERBEKE
Engines & Generators
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