freightliner 108SD, Руководство пользователя

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•
The On/Off switch (ENG BRK), is used to turn
the engine brake on and off. See
Fig. 10.4 .
When the engine brake is on, an amber light
will illuminate behind the switch.
•
The engine brake intensity switch (HI/MED/LO
or, in some cases, HI/LO) controls the amount
of engine braking. When the panel lights are
on, the ENG BRK legend is backlit in green.
Since the engine brake is most effective at rated en-
gine speed, gear selection is very important. Gearing
down the vehicle within the limits of the rated engine
speed makes the engine brake more effective. Rec-
ommended engine braking speed is above 1800 rpm
and below the rated speed.
WARNING
The engine brake must be disengaged when
shifting gears using the clutch pedal. If the en-
gine brake is engaged when the transmission is
in neutral, the braking power of the engine brake
can stall the engine, which could result in loss of
vehicle control, possibly causing personal injury
and property damage.
"Control speed" is the speed at which the engine
brake performs 100 percent of the required downhill
braking, resulting in a constant speed of descent.
The control speed varies, depending on vehicle
weight and the downhill grade.
For faster descent, select a higher gear than that
used for control speed. Service brakes must then be
used intermittently to prevent engine overspeed and
to maintain desired vehicle speed.
For slower descent, select a lower gear, being care-
ful not to overspeed the engine. Occasional deactiva-
tion of the engine brake may be necessary to main-
tain the designated road speed under these
conditions.
If the engine is equipped with both cruise control and
an engine brake, the engine brake can operate auto-
matically while in cruise control mode. If the cruise
control/engine brake function is turned on in the
DDEC VI system programming, the engine brake will
come on low when the set road speed increases a
few miles-per-hour (kilometers-per-hour) above the
cruise set speed. The maximum amount of braking is
selected with the dash switches. When the vehicle
returns to the set cruise speed, the engine brake will
turn off.
The engine brake will only operate when the accel-
erator pedal is fully released. Depressing the clutch
will also prevent the engine brake from operating.
Vehicles equipped with ABS have the ability to turn
the engine brake off if wheel slip is detected. The
engine brake will automatically turn back on once
wheel slip is no longer detected.
The DDEC VI system will deactivate the engine
brake when the engine speed falls below 1000 rpm
or when the vehicle slows down to a preset speed,
depending on DDEC programming. This prevents
stalling the engine.
Engine Brake Operation
Depending on the brake type, the engine brake may
be disabled when engine temperature falls below a
set level.
NOTICE
Do not allow the engine to exceed 2500 rpm. Se-
rious engine damage could result.
To activate the engine brake after the engine is
warmed up and the vehicle is in motion:
1. Remove your feet from both the clutch and
throttle pedals.
2. Press the On/Off switch to toggle the engine
brake on. See
Fig. 10.4 . The engine brake will
engage at the rate last set on the brake intensity
switch.
3.
Move the intensity switch to the desired intensity.
10/17/2001
f610588
1 2
1. Engine Brake On/Off
2. Engine Brake Intensity Switch
Fig. 10.4, Engine Brake Switches
Optional Engine Systems
10.4