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STARTING PROCEDURES ± DIESEL ENGINES
Before starting your vehicle, adjust your seat, adjust both
inside and outside mirrors, and fasten your seat belts.
The starter should not be operated for more than 15-
second intervals. Waiting a few minutes between such
intervals will protect the starter from overheating.
WARNING!
Be sure to turn off the engine and remove the key
from the ignition switch if you want to rest or sleep
in your vehicle. Accidents can be caused by inadvert-
ently moving the shift lever or by pressing the
accelerator pedal. This may cause excessive heat in
the exhaust system, resulting in overheating and
vehicle fire which may cause serious or fatal injuries.
WARNING!
Do not leave children or animals inside parked
vehicles in hot weather. Interior heat build up may
cause serious injury or death.
Automatic Transmission ± If Equipped
Start the engine with the shift lever in NEUTRAL or
PARK position. Apply the brake before shifting to any
driving range.
The CumminstDiesel engine is equipped with several
features designed to assist cold weather starting and
operation:
²The engine block heater is a resistance heater installed
in the water jacket of the engine just above and behind
the oil filter. It requires a 110±115 volt AC electrical
outlet with a grounded, three-wire extension cord.
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NOTE:The engine block heater cord is a factory in-
stalled option. If your vehicle is not equipped, heater
cords are available from your authorized Mopartdealer.
²A 12±volt heater built into the fuel filter housing aids
in preventing fuel gelling. It is controlled by a built-in
thermostat.
²A heated intake air system both improves engine
starting and reduces the amount of white smoke
generated by a warming engine.
Manual Transmission ± If Equipped
Apply the parking brake, place the shift lever in NEU-
TRAL and depress the clutch pedal to the floor before
starting the vehicle. This vehicle is equipped with a
clutch interlocking ignition system. It will not start unless
the clutch is fully depressed.
Normal Starting Procedure ± Engine Manifold Air
Temperature Above 66ÉF (19ÉC)
Observe the instrument panel cluster lights when starting
the engine.
1. Always apply the parking brake.
2. Shift into PARK for an automatic transmission. For
vehicles equipped with manual transmissions, fully de-
press and hold the clutch pedal and shift into NEUTRAL.
3. Turn the ignition key to the ON position and watch the
instrument panel cluster lights.
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Block Heater Usage
A.Temperatures below 0ÉF (-18ÉC)
²Block Heater Required for 15W-40
²Block Heater Recommended for 5W-40
B.Temperatures below - 20ÉF (-29ÉC)
²Block Heater Required for 5W-40
Winter Front Usage
If a winter front or cold weather cover is to be used, a
percentage of the total grille opening area must be left
uncovered to provide sufficient air flow to the charge air
cooler and automatic transmission oil cooler. The per-
centage of opening must be increased with the increasing
ambient air temperature and/or engine load. If the
cooling fan can be heard cycling frequently, increase the
size of the opening in the winter front. A suitable cold
weather cover is available from your Mopartdealer.
Battery Blanket Usage
A battery loses 60% of its cranking power as the battery
temperature decreases to 0ÉF (-18É). For the same de-
crease in temperature, the engine requires twice as much
power to crank at the same RPM. The use of 120 VAC
powered battery blankets will greatly increase starting
capability at low temperatures. Suitable battery blankets
are available from your authorized Mopartdealer.
Arctic Operation
Where there are no provisions to keep the engine warm
when it is operating in ambient temperatures consistently
below (-10ÉF/-23ÉC), use 5W-40syntheticengine oil and
fuel that meets the requirements in Section 7, ªMainte-
nance Procedures,º Engine Oil Selection.
Engine Warm-Up
Avoid full throttle operation when the engine is cold.
When starting a cold engine, bring the engine up to
operating speed slowly to allow the oil pressure to
stabilize as the engine warms up.
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NOTE:An optional driver-controlled high idle speed is
available on automatic transmission equipped vehicles
with speed control. This feature allows the driver to
select an elevated idle speed between 1100 and 1500
rpms. Your dealer can enable this feature.
The optional driver-controlled high idle speed will help
increase cylinder temperatures and provide additional
cab heat, however, may still cause the exhaust aftertreat-
ment system to not properly regenerate. Extended peri-
ods of idle time should be avoided.
NOTE:
²If ambient temperatures are low and the coolant
temperature is below 200ÉF (93ÉC), the engine idle
speed will slowly increase to 1000 RPM after 2 minutes
of idle, if the following conditions are met:
²foot is off brake pedal and throttle pedal
²automatic transmission is in Park (P)
²vehicle speed is zero
²Applying the throttle will cancel fast idle
²If the engine is equipped with an exhaust brake,
operating the exhaust brake at idle will greatly im-
prove warm up rate and will help keep the engine
close to operating temperature during extended idle.
CAUTION!
Use of aftermarket exhaust brakes is not recom-
mended and could lead to engine damage
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Stopping The Engine
Idle the engine a few minutes before routine shutdown.
After full load operation, idle the engine 3 to 5 minutes
before shutting it down. This idle period will allow the
lubricating oil and coolant to carry excess heat away from
the combustion chamber, bearings, internal components,
and turbocharger. This is especially important for turbo-
charged, charge air cooled engines.
NOTE:During engine shutdown on vehicles equipped
with manual transmissions, it is normal for the diesel
engine to resonate heavily for a moment during engine
shut off. When the engine is connected to a manual
transmission, this resonance causes loud gear rattle from
the transmission. This is commonly referred to as ªshut
down rattleº. The manufacturer recommends performing
engine shut down with the clutch pedal pushed to the
floor (clutch disengaged). When engine shut down is
performed in this manner the rattle is reduced (not
eliminated).Driving
ConditionLoadTurbo-
charger
TemperatureIdle Time
(min.) Be-
fore Engine
Shutdown
Stop and
GoEmpty Cool Less than
One
Stop and
GoMedium One
Highway
SpeedsMedium Warm Two
City Traffic Maximum
GCWRThree
Highway
SpeedsMaximum
GCWRFour
Uphill
GradeMaximum
GCWRHot Five
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Engine Speed Control
CAUTION!
Prevent overspeeding the engine going down hill.
When descending steep grades, use a combination of
gears and service brakes to control vehicle/engine
speed. Overspeed can cause severe engine damage.
Operating Precautions
Avoid Overheating The Engine
The temperature of the coolant (a mixture of 50%
ethylene-glycol and 50% water) must not exceed the
normal range of the temperature gauge (240ÉF/116ÉC)
with a 16 psi (110 kPa) radiator cap.
Usually the coolant temperature indicated during opera-
tion will be to the left of center in the normal range of the
gauge.
Avoid Low Coolant Temperature Operation
Continual operation at low coolant temperature below
the normal range on the gauge (140ÉF/60ÉC) can be
harmful to the engine. Low coolant temperature can
cause incomplete combustion which allows carbon and
varnish to form on piston rings and injector nozzles.
Also, the unburned fuel can enter the crankcase, diluting
the lubricating oil and causing rapid wear to the engine.
Cooling System Tips Ð Automatic Transmission
To reduce potential for engine and transmission over-
heating in high ambient temperature conditions, take the
following actions:
²City Driving Ð
when stopped, put transmission in neutral and increase
engine idle speed.
²Highway Driving Ð
reduce your speed.
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²Up Steep Hills Ð
select a lower transmission gear, but try and keep the
torque converter clutch engaged.
²Air Conditioning Ð
turn it off temporarily.
Do Not Operate The Engine With Low Oil
Pressure
When the engine is at normal operating temperature, the
minimum oil pressures required are:
Idle 700 to 800 RPM............... 10psi(69kPa)
Full speed and load.............. 30psi(207 kPa)
CAUTION!
If oil pressure falls to less than normal readings, shut
the engine off immediately. Failure to do so could
result in immediate and severe engine damage.
Do Not Operate The Engine With Failed Parts
Practically all failures give some warning before the parts
fail. Be on the alert for changes in performance, sounds,
and visual evidence that the engine requires service.
Some important clues are:
²engine misfiring or vibrating severely
²sudden loss of power
²unusual engine noises
²fuel, oil or coolant leaks
²sudden change, outside the normal operating range, in
the engine operating temperature
²excessive smoke
²oil pressure drop
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DIESEL EXHAUST BRAKE (ENGINE BRAKING) ±
IF EQUIPPED
The exhaust brake feature will only function when the
driver turns the exhaust brake switch to the ON position.
Once the switch is in the ON position and the vehicle is
moving faster than 5 mph (8 km/h); the exhaust brake
will automatically operate when the driver removes
pressure from the accelerator pedal. Exhaust braking is
most effective when the engine RPM is higher. The
automatic transmission has been programmed to down-
shift more aggressively when the exhaust brake is en-
abled to increase brake performance.
Exhaust Brake Switch
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