Egr Flow - International VT 275 V6 Manual

EGR Valve
• The EGR valve consists of a stepper motor
and two poppet valves connected by a
common shaft. When inserted into the
manifold, the valve aligns with the port in
the intake manifold that connects to the
EGR cooler. When the valve is open,
exhaust gases flow from the cooler and
enter the manifold through the open
poppet valves.
• The EGR valve opens when the ECM
commands the EGR drive module to
position the valve. The drive module then
sends signals to the stepper motor to
produce armature rotation. When the
armature turns, the poppet valves move off
their seats.
I I N N T T A A K K E E M M A A N N I I F F O O L L D D
I I N N T T A A K K E E M M A A N N I I F F O O L L D D
C C O O M M M M O O N N S S H H A A F F T T
C C O O M M M M O O N N S S H H A A F F T T
P P O O P P P P E E T T
P P O O P P P P E E T T
V V A A L L V V E E S S
V V A A L L V V E E S S
E E G G R R V V A A L L V V E E
E E G G R R V V A A L L V V E E
E E G G R R C C O O O O L L E E R R
E E G G R R C C O O O O L L E E R R
International ® VT 275 V6 Engine
AIR MANAGEMENT SYSTEM
S S T T E E P P P P E E R R M M O O T T O O R R H H O O U U S S I I N N G G
S S T T E E P P P P E E R R M M O O T T O O R R H H O O U U S S I I N N G G

EGR Flow

• The ECM-controlled
Recirculation (EGR) valve meters cooled
exhaust gases in the intake charge air to
reduce Oxides of Nitrogen
emissions. Exhaust gases from the exhaust
pipe assembly are directed to the EGR
cooler. Gases flowing through exhaust
passages in the cooler lose heat energy to
engine coolant flowing through the coolant
passages in the cooler. The cooled
exhaust gases travel from the cooler into a
passage cast into the intake manifold. The
EGR valve fits into the exhaust passage
and is sealed with two O-rings.
• When the EGR valve opens, exhaust
gases flow into the intake charge air from
both the top and bottom of the passage,
providing better distribution of the gases.
Exhaust Gas
(NOx)
47