User Manual

SERIES 50 OPERATOR'S GUIDE
ENGINE BRAKE SYSTEM
Certain Series 50 vehicle engines
are equipp ed with engine brakes,
commonly referred to as retarders.
Before operating the vehicle, you
must familiarize yourself with the
retarder system to obtain optimum
benefit from it. Engine brake control
systems may vary slightly, d epending
on the engine brake configuration and
cab design. However, basic operator
controls are similar for all models.
Driver Control Switches
Vehicles with manual transmissions
allow the dr iver to turn the engine
brake on and off an d select a low,
medium or high level of braking. Tw o
types of switches are available.
Low/High Switch
The Low setting on this switch
activates three (3) brake cylinders,
supplying approximately 50% of
normal engine braking horsepower.
The High setting activates all six
(6) cylinders, providing full engine
braking horsepower.
Low/Med/High Switch
The Low setting on this switch
activates two (2) brake cylinders,
yielding about on e-th ird engine
braking horsepower. The Medium
activates four (4) cylinders, sup ply ing
about two-thirds engine braking
horsepower. The High setting
activates all six (6) c ylinders,
providing full braking horsepower.
Clutch Pedal and Throttle
Position Controls
Engine brakes have two additional
controls, one activated by the position
of the clutch pedal and the other
activated by the position of the
throttle. These controls permit fully
automatic operation of the engine
braking system.
Engine Brake Operation
NOTE:
The engine brake retarder system
depends on a full-pressure flow
of warm eng ine lubricating oil for
proper lubrication of moving parts
and optimum performance. It is
importanttoallowtheenginetoreach
full operating temperature before
switching on the engine brake system.
Under normal driving conditions the
engine brake system is left in the ON
position. However, this should change
if roads become wet or slippery.
All information subject to change without notice. (Rev. 01/04) 41
DDC-SVC-MAN-0058 Copyright © 2004 DE TROIT DIESEL CORPORATION