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DIESEL ENGINE INFORMATION
The Diesel engine fuel system consists of:
•a frame-mounted electric fuel supply pump
•an engine mounted fuel filter/water separator
•a fuel restriction sensor
•a unit injector for each cylinder
The combination fuel filter/water separator removes both water and
impurities from the fuel. The filter should be changed at the
recommended service interval. Refer to the scheduled maintenance guide
for more information. The filter bowl should be drained at regular
intervals or when the WATER IN FUEL light illuminates in the
instrument cluster.
The fuel injectors are located in the center of the combustion chambers
in the cylinder head between the rocker arm assemblies. The glow plug
system and fuel injection system are controlled through the Powertrain
Control Module (PCM).
Fuel is drawn from the fuel tank by a frame-mounted electric fuel pump.
The fuel pump provides pressurized fuel to the engine and is
electronically controlled by the fuel pump PCM relay. The fuel pump
contains a pressure relief valve for overpressure protection in the event
of restricted flow.
Lubrication system
It is important to change the engine oil at the recommended service
intervals, because oil viscosity is important in maintaining the oil
pressure required to actuate the fuel injectors. Extended oil change
intervals can negatively affect engine performance and fuel economy.
Pressurized oil from the turbocharger is also used to actuate an exhaust
backpressure warm-up system (if equipped). Pressurized oil from the
turbocharger is routed to the exhaust backpressure actuator. During
exhaust backpressure operation, the engine’s sound will be altered and
you may notice a change in engine performance while it’s engaged. This
function occurs only during cold weather warm-up cycle.
Fast start glow plug system
The glow plug system consists of:
•eight glow plugs
•the glow plug relay
Diesel information
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WATER IN FUEL
•E-Series
•F-250/350/450/550, Excursion
During refueling, it is possible for water-contaminated diesel fuel to be
pumped into your tank. Your vehicle fuel system is equipped with a fuel
filter/water separator to remove water from the fuel. The WATER IN
FUEL light will illuminate when the ignition is turned to START (as part
of the light function check) and when the fuel filter/water separator has
a significant quantity of water in it.
If the light illuminates when the engine is running, stop the vehicle as
soon as safely possible, shut off the engine, then drain the filter bowl.
Refer to theGeneral maintenancechapter for drain procedure.
Allowing water to stay in the system could result in extensive damage to,
or failure of, the fuel injection system.
Do not drain the water separator while the engine is running.
Fuel may ignite if the separator is drained while the engine is
running or the vehicle is moving.
ENGINE AIR FILTER (F-250/350/450/550 & EXCURSION)
The engine air filter warning light
illuminates when the air filter
restriction gauge reaches the
CHANGE FILTER mark.
The vehicle may be driven with the engine air filter warning light
illuminated for up to 400 km (250 miles) without damaging the engine or
related components. However, the air filter elementmustbe replaced at
the earliest opportunity. Refer toAir filter restriction gaugein the
Diesel informationchapter for more information.
Warning lights
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Do not use fuel intended for agricultural use (agricultural fuel is
dyed red), home heating oil or any Diesel fuel not intended for
highway use. Damage to the fuel injection system or engine can
occur if an improper fuel is used.
Do not add gasoline, gasohol or alcohol to Diesel fuel. This practice
creates a serious fire hazard and engine performance problems.
It should not be necessary to add any aftermarket additives to your fuel
tank if you use a properly formulated Diesel fuel that meets the ASTM D
975 industry specification. Aftermarket additives can damage the injector
system or engine.
Do not blend used engine oil with Diesel fuel under any circumstances.
Blending used oil with the fuel will significantly increase your vehicle’s
exhaust emissions and reduce engine life due to increased internal wear.
Do not crank the engine for more than 30 seconds at a time as
damage to the starter motor may result.
If the engine fails to start in 30 seconds, turn the key to the OFF
position and wait 30 seconds before trying again.
Truck stops have pumps and nozzles designed for larger, heavy-duty
trucks. When refueling at truck stops: if the nozzle shuts off repeatedly
when refueling, wait 5–10 seconds; then use a slower rate of flow (don’t
depress the nozzle trigger as far).
If air is allowed to enter the fuel system (during fuel filter change or if
you run out of fuel) the engine will purge the trapped air as it runs. The
engine may run rough and produce white smoke while air is in the
system. This is normal and should correct itself in a short time.
An engine that suddenly becomes noisy or operates poorly after a fuel fill
could be using substandard fuel (i.e., high water content, low cetane
rating or gasoline in the fuel). Diesel fuel should be purchased from a
reputable station which sells a large amount of Diesel fuel.
Care should be taken whenever Diesel fuel is stored. Use only clean,
approved containers which will prevent the entry of dirt or water.
Diesel fuel must not be stored in a galvanized container. The fuel will
dissolve the zinc in a galvanized container. The zinc will then remain in
solution until it is run through the engine where it will be deposited in
the fuel injectors causing expensive-to-repair damage.
General maintenance information
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