7-1
GRT8100 SERVICE MANUAL POWER TRAIN
Published 3/26/2018, Control # 596-05
SECTION 7
POWER TRAIN
SECTION CONTENTS
Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-2
Electronic Control System. . . . . . . . . . . . . . . . . . . 7-4
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4
Engine Control System Indicator Lights . . . . . . . . 7-4
Fuel System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
Air Intake and Exhaust System . . . . . . . . . . . . . . . 7-7
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-7
Air Intake. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-7
Charge-Air Cooler System . . . . . . . . . . . . . . . . . 7-12
Exhaust System . . . . . . . . . . . . . . . . . . . . . . . . . 7-13
Slip Joint Exhaust Connectors - Tier 3 and 4 . . . 7-13
Water Cooling System . . . . . . . . . . . . . . . . . . . . . 7-16
Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-16
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-16
Radiator Fill and Servicing. . . . . . . . . . . . . . . . . . 7-20
Drive Train . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-22
Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-22
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-22
Transmission/Torque Converter . . . . . . . . . . . . . 7-23
Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-23
Theory of Operation. . . . . . . . . . . . . . . . . . . . . . . 7-23
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-24
Towing or Pushing . . . . . . . . . . . . . . . . . . . . . . . . 7-28
ENGINE
Description
The engine is a Cummins QSB 6.7 diesel engine. This
Service Manual does not include detailed information on the
engine itself. A separate manual as prepared in detail by the
engine manufacturer, is supplied with this Service Manual.
However, a short description and maintenance of certain
components of the fuel system, air intake system, and water
cooling system is provided in this section.
The engine is electronically controlled by the Electronic
Control Module (ECM); it is the control center of the system.
It processes all of the inputs and sends commands to the fuel
systems as well as vehicle and engine control devices.
Engine speed is controlled by the foot throttle pedal in the
cab. It controls engine RPM which increases or decreases
proportionately with the amount of foot pressure applied to
the pedal. Engine speed is also controlled by the idle switch,
which is a three position rocker switch located on the front of
the steering column. The idle switch allows the operator to
infinitely vary and hold the engine speed between the
engine’s minimum and maximum idle settings (refer to
Section 3, Operating Controls and Procedures in the
applicable Operation Manual for details on the operation of
the idle switch). The foot throttle pedal is electrically
connected to the superstructure control module which sends
the signal to the engine ECM via the J1939 data link.
The engine and its components are enclosed in a hood
assembly with a grill in the rear of the hood for adequate air
circulation. Access to the engine is gained through a door
assembly in the top of the hood that opens from both sides.
The air intake filter is mounted on the right rear hood
assembly. The muffler is mounted on the left side on the rear
outrigger box.
The engine is equipped with electric air heating elements
located in the engine intake air stream to aid in cold starting
and reduce white smoke at start-up. In preheat mode, the
engine should not be cranked until Wait-to-Start Lamp turns
off. The Wait-to-Start Lamp is illuminated during the preheat
time that takes place when the ignition switch is in the ON
position during cold weather starting. The ECM checks
information it receives from various sensors on the engine to
determine how long to energize the air heater before
extinguishing the Wait-to-Start Lamp. Once the engine is
started, the electric air heating element will be energized
again for a time period determined by intake air temperature.
WARNING
Do not spray starting fluid into the air inlet. The spray will
contact the heater elements and could explode causing
personal injury.
To Next Page
Loading...
Need help?
General
