Westerbeke 8.0 KW-60Hz SBEG Operator's Manual page 29

THROTTLE BODY ASSEMBLY
PUSH ON
SPAOE CONNECTION
MAP SENSOR
SCHRADER
VALVE
FROM THE THERMOSTAT ASSEMBLY
i' ..
FUEL INJECTOR FUEL
PRESSURE
AIR TEMPERATURE
SENSOR
MANIFOLD
RETURN
DESCRIPTION
The above illustration shows the throttle body assembly
attached to the intake manifold.
An electronic control unit
(ECU) controls the fuel injector
and the throttle actuator.
The ECU is supplied with engine operating conditions from
sensors that monitor intake air temperature, engine coolant
temperature, map sensor (intake manifold absolute pressure),
engine rpm and battery voltage.
The ECU interprets this information to determine the
appropriate injector pulse rate and throttle opening position.
A high pressure fuel pump supplies fuel to the area around
the injector and the regulator maintains the fuel pressure in
that area at 35 - 40 PSI.
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 deteimined by the
ECU.
Air flow into the intake manifold is through the flame
arrester/air filter and 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 and to bleed air from that area after fuel
system servicing.
An air intake heater is positioned in the intake to heat the
incoming air during a cold start.
Engines.
&
Generators
18