coolant temperature Ram 2500 2016 Diesel Supplement

5. After engine start-up, check to see that there is oilpressure.
6. Allow the engine to idle about three minutes until the manifold heaters have completed the post-heat cycle.
7. Release the parking brake and drive.
NOTE:
• Engine idle speed will automatically increase to 1,000
RPM and engage the Variable Geometry Turbocharger
at low coolant temperatures to improve engine warm-
up.
• The engine may not automatically crank after the
engine Wait To Start telltale goes off if a door or the
hood is ajar.
• If the engine stalls, or if the ignition switch is left ON
for more than two minutes after the “Wait To Start
Light” goes out, reset the grid heaters by turning the ignition switch to the OFF position for at least five
seconds and then back ON. Repeat steps 1 through 7 of
“Keyless Enter-N-Go Starting Procedure – Engine
Manifold Air Temperature Below 66° F (19° C).”
Extreme Cold Weather
The Cummins diesel engine is equipped with several
features designed to assist cold weather starting and
operation:
•
The 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.
NOTE: The engine block heater cord is a factory installed
option. If your vehicle is not equipped, heater cords are
available from your authorized MOPAR dealer.
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STARTING AND OPERATING 265

2. While theWait To Start” telltale is on, the EVIC/DID
will additionally display a gauge or bar whose initial
length represents the full Wait To Starttime period.
Its length will decrease until it disappears when the
Wait To Start time has elapsed.
CAUTION!
If the “Water in Fuel Indicator Light” remains on, DO
NOT START engine before you drain the water from
the fuel filters to avoid engine damage. Refer to
“Maintenance Procedures/Draining Fuel/Water Sepa-
rator Filter” in “Maintaining Your Vehicle” for fur-
ther information.
3. After the “Wait To Start” telltale goes off, turn the ignition switch to the START position. Do not press the
accelerator during starting.
CAUTION!
Do not crank engine for more than 15 seconds at a
time or starter motor damage may result. Turn the
ignition switch to the OFF position and wait at least
two minutes for the starter to cool before repeating
start procedure.
4. After engine start-up, check that the oil pressure warning light has turned off.
5. Allow the engine to idle about three minutes until the manifold heaters have completed the post-heat cycle.
6. Release the parking brake and drive.
NOTE:
• Engine idle speed will automatically increase to 1,000
RPM and engage the Variable Geometry Turbocharger
at low coolant temperatures to improve engine warm-
up.
268 STARTING AND OPERATING

NOTE:Excessive white smoke and poor engine perfor-
mance will result if manifold heaters are not recycled.
2. Heat generated by the manifold heaters dissipates rapidly in a cold engine. If more than two minutes
pass between the time the “Wait To Start” telltale turns
off and the engine is started, recycle the manifold
heaters by turning the ignition switch to the OFF
position for at least five seconds and then back ON.
3. If the vehicle is driven and vehicle speed exceeds 19 mph (31 km/h) before the manifold heater post-
heat (after start) cycle is complete, the manifold heat-
ers will shut off.
4. If the engine is started before the “Wait To Start” telltale turns off, the preheat cycle will turn off.
5. If the engine is cranked for more than 10 seconds, the post-heat cycle will turn off. NOTE:
•
Engine idle speed will automatically increase to 1,000
RPM and engage the Variable Geometry Turbocharger
at low coolant temperatures to improve engine warm-
up.
• When a diesel engine is allowed to run out of fuel or
the fuel gels at low temperatures, air is pulled into the
fuel system. If your engine has run out of fuel, refer to
“Maintenance Procedures/Priming If The Engine Has
Run Out Of Fuel” in “Maintaining Your Vehicle” for
further information.
• If the engine stalls, or if the ignition switch is left ON
for more than two minutes after the “Wait To Start”
telltale goes out, reset the grid heaters by turning the
ignition switch to the OFF position for at least five
seconds and then back ON. Repeat steps 1 through 5 of
“Starting Procedure – Engine Manifold Air Tempera-
ture Below 66°F (19°C).”
270 STARTING AND OPERATING

NOTE:High-speed, no-load running of a cold engine can
result in excessive white smoke and poor engine perfor-
mance. No-load engine speeds should be kept under
1,200 RPM during the warm-up period, especially in cold
ambient temperature conditions.
Your vehicle is equipped with a turbo speed limiter, this
feature limits the engine speed to 1,200 RPM when
engine coolant temperatures are below 70°F (21°C). This
feature is designed to protect the turbocharger from
damage and will only operate in PARK or NEUTRAL.
If temperatures are below 32°F (0°C), operate the engine
at moderate speeds for five minutes before full loads are
applied. NOTE:
If ambient temperatures are low and the coolant
temperature is below 180°F (82°C), the engine idle speed
will slowly increase to 1,000 RPM after two minutes of
idle, if the following conditions are met:
• Foot is off brake pedal and throttle pedal.
• Automatic transmission is in PARK.
• Vehicle speed is 0 mph (0 km/h).
• Applying the throttle will cancel fast idle.
• 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.
Engine Idling
Avoid prolonged idling, long periods of idling may be
harmful to your engine because combustion chamber
temperatures can drop so low that the fuel may not burn
completely. Incomplete combustion allows carbon and
5
STARTING AND OPERATING 275

Operating Precautions
Avoid Overheating The Engine
The temperature of the engine coolant (antifreeze) (a
mixture of 50% ethylene-glycol and 50% water) must not
exceed the normal range of the temperature gauge 240°F
(116°C) with a 21 psi (145 kPa) coolant pressure cap.
Usually the engine coolant (antifreeze) temperature indi-
cated during operation will be to the left of center in the
normal range of the gauge.
Avoid Low Coolant Temperature Operation
Continual operation at low engine coolant (antifreeze)
temperature below the normal range on the gauge 140°F
(60°C) can be harmful to the engine. Low engine coolant
(antifreeze) temperature can cause incomplete combus-
tion which allows carbon and varnish to form on pistonrings 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 — Automatic Transmission
To reduce potential for engine and transmission over-
heating in high ambient temperature conditions, take the
following actions:
•
City Driving —
When stopped, shift the transmission into NEUTRAL
and increase engine idle speed.
• Highway Driving —
Reduce your speed.
• Up Steep Hills —
Select a lower transmission gear.
• Air Conditioning —
Turn it off temporarily.
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STARTING AND OPERATING 279

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 10 psi (69 kPa)
Full speed and load 30 psi (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
All engine 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:•
Engine misfiring or vibrating severely.
• Sudden loss of power.
• Unusual engine noises.
• Fuel, oil or coolant leaks.
• Sudden change, outside the normal operating range, in
the engine operating temperature.
• Excessive smoke.
• Oil pressure drop.
ENGINE BLOCK HEATER — IF EQUIPPED
The engine block heater warms engine coolant and
permits quicker starts in cold weather. Connect the heater
cord to a ground-fault interrupter protected 110–115 Volt
AC electrical outlet with a grounded, three-wire exten-
sion cord.
280 STARTING AND OPERATING

The engine block heater cord is routed under the hood to
the right side and can be located just behind the grille
near the headlamp.
NOTE:The engine block heater cord is a factory installed
option. If your vehicle is not equipped, heater cords are
available from your authorized MOPAR dealer.
The block heater must be plugged in at least one hour to
have an adequate warming effect on the coolant.
WARNING!
Remember to disconnect the cord before driving.
Damage to the 110–115 Volt electrical cord could
cause electrocution.
NOTE: The block heater will require 110 Volts AC and 6.5
Amps to activate the heater element.
Block Heater Usage
For ambient temperatures below 0°F (-18°C), engine
block heater usage is recommended.
For ambient temperatures below –20°F (-29°C), engine
block heater usage is required.
DIESEL EXHAUST BRAKE (ENGINE BRAKING)
The purpose of the exhaust brake (engine braking) fea-
ture is to supply negative (braking) torque from the
engine. Typically, the engine braking is used for, but not
limited to, vehicle towing applications where vehicle
braking can be achieved by the internal engine power,
thereby sparing the mechanical brakes of the vehicle.
Benefits of the exhaust brake are:
• Vehicle driving control.
• Reduced brake fade.
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STARTING AND OPERATING 281

The automatic transmission will downshift more aggres-
sively in TOW/HAUL mode when the exhaust brake is
enabled to increase brake performance.
CAUTION!
Use of aftermarket exhaust brakes is not recom-
mended and could lead to engine damage
WARNING!
Do not use the exhaust brake feature when driving in
icy or slippery conditions as the increased engine
braking can cause the rear wheels to slide and the
vehicle to swing around with the possible loss of
vehicle control, which may cause an accident possi-
bly resulting in personal injury or death.
NOTE: For optimum braking power it is recommended
to use the exhaust brake while in TOW/HAUL mode. The exhaust brake feature can also be used to reduce the
engine warm up time. To use the exhaust brake as a
warm-up device, the vehicle must be stopped or moving
less than 5 mph (8 km/h), the
Exhaust Brake Indicator
must be on, and the coolant temperature must be below
180°F (82°C) and ambient temperature below 60°F (16°C).
Automatic Smart Exhaust Brake
Automatic Exhaust Brake technology delivers smoother,
less aggressive exhaust braking characteristics during
downhill descents. Although it can apply full exhaust
braking force if needed, Automatic Exhaust Brake may
not apply obvious braking if the vehicle speed is not
increasing. Automatic Exhaust Brake is intended to main-
tain vehicle speed, while Full Exhaust Brake is intended
to reduce vehicle speed.
Automatic Exhaust Brake can be enabled by pushing the
exhaust brake button again anytime after the normal Full
Exhaust Brake has been turned on. The “Exhaust Brake
5
STARTING AND OPERATING 283

CAUTION!(Continued)
negative post. Battery posts are marked (+) positive
and negative (-) and are identified on the battery
case. Also, if a “fast charger” is used while the battery
is in vehicle, disconnect both vehicle battery cables
before connecting the charger to the battery. Do not
use a “fast charger” to provide starting voltage.
WARNING!
Battery posts, terminals, and related accessories con-
tain lead and lead compounds. Always wash hands
after handling the battery.
Battery Blanket Usage
A battery loses 60% of its cranking power as the battery
temperature decreases to 0°F (-18°). For the same de-
crease in temperature, the engine requires twice as much
power to crank at the same RPM. The use of 120 Volt AC powered battery blankets will greatly increase starting
capability at low temperatures. Suitable battery blankets
are available from your authorized MOPAR dealer.
Cooling System
WARNING!
You or others can be badly burned by hot engine
coolant (antifreeze) or steam from your radiator. If
you see or hear steam coming from under the hood,
do not open the hood until the radiator has had time
to cool. Never try to open a cooling system pressure
cap when the radiator is hot.
Engine Coolant Checks
Check the engine coolant (antifreeze) protection every 12
months (before the onset of freezing weather, where
applicable). If the engine coolant (antifreeze) is dirty or
rusty in appearance, the system should be drained,
354 MAINTAINING YOUR VEHICLE

flushed and refilled with fresh coolant. Check the front of
the A/C condenser (if equipped) or radiator for any
accumulation of bugs, leaves, etc. If dirty, clean by gently
spraying water from a garden hose vertically down the
face of the A/C condenser (if equipped) or the back of the
radiator core.
Check the engine cooling system hoses for brittle rubber,
cracking, tears, cuts and tightness of the connection at the
coolant recovery bottle and radiator. Inspect the entire
system for leaks.
With the engine at normal operating temperature (but
not running), check the cooling system pressure cap for
proper vacuum sealing by draining a small amount of
engine coolant (antifreeze) from the radiator drain cock.
The radiator drain cock is located in the lower radiator
tank. If the cap is sealing properly, the engine coolant(antifreeze) will begin to drain from the coolant expan-
sion bottle. DO NOT REMOVE THE COOLANT PRES-
SURE CAP WHEN THE COOLING SYSTEM IS HOT.
Cooling System — Drain Flush And Refill
If the engine coolant (antifreeze) is dirty or contains a
considerable amount of sediment, clean and flush with a
reliable cooling system cleaner. Follow with a thorough
rinsing to remove all deposits and chemicals. Properly
dispose of old engine coolant (antifreeze).
Refer to the “Maintenance Schedule” for the proper
maintenance intervals.
Selection Of Coolant
Refer to “Fluids, Lubricants, And Genuine Parts” in
“Maintaining Your Vehicle” for further information.
7
MAINTAINING YOUR VEHICLE 355