Engine Description - Navistar MaxxForce DT 9 Operation And Maintenance Manual

Engine Specifications (cont.)

Engine Description

MaxxForce® DT, 9, and 10 are inline six cylinder diesel engines
which have been designed for increased durability, reliability, and
ease of maintenance.
Air Management System
The MaxxForce® DT, 9, and 10 engines use an electronically
controlled two stage turbocharging system consisting of a
high-pressure and low-pressure turbocharger. The high and
low-pressure turbochargers are installed as an assembly on the
exhaust manifold.
A Charge Air Cooler (CAC) is an air-to-air heat exchanger which
cools and increases the density of the air charge. In addition
to the CAC, the MaxxForce® 9 and 10 diesel engines have
an engine mounted interstage cooler. The cooler has a low
temperature radiator and a low temperature thermostat.
The Exhaust Gas Recirculation (EGR) system circulates cooled
exhaust into the intake air stream in the intake manifold. This
cools the combustion process and reduces the formation of NO
engine emissions.
Cold Start Assist
The Inlet Air Heater (IAH) system warms the incoming air supply
to aid cold engine starting and reduce white smoke during
warm-up. The IAH system will initially illuminate the WAIT TO
SECTION 1 – ENGINE SYSTEMS
START lamp. When the lamp turns off, the engine can be
started.
Crankcase Assembly
The camshaft is supported by four insert bushings pressed into
the crankcase. The camshaft gear is driven from the front of the
engine. A thrust flange is located between the camshaft and the
drive gear. The overhead valve train includes mechanical roller
lifters, push rods, rocker arms, and dual valves that open using
a valve bridge.
A gerotor lube oil pump is mounted on the front cover and
is driven by the crankshaft.
engine components and the high-pressure injection system. All
MaxxForce® DT, 9, and 10 engines use an engine oil cooler
and spin-on engine oil filter.
The MaxxForce® DT engine uses a one piece aluminum alloy
piston. The MaxxForce® 9 and 10 engines use a one piece steel
piston. The pistons have a 0.0 offset and are fully symmetric.
The one piece crankcase uses replaceable wet cylinder sleeves
X
that are sealed by a single crevice seal. Some applications
include a crankcase ladder which is designed to absorb heavier
loads and reduce engine noise.
A closed crankcase breather system uses an engine mounted
oil separator to return oil to the crankcase and vent crankcase
pressure into the intake system.
Form No. 1172040R1
Printed in the United States of America
Pressurized oil is supplied to
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