
What Fuel to Use in Canada
Canadian fuels are blended for seasonal changes.
Diesel Type “A” fuel is blended for better cold
weather starting (below 0°F or−18°C); however,
you may notice some power and fuel economy
loss. If Type “A” fuel is used in warmer
temperatures, stalling and hard starting may
occur. Diesel Type “B” fuel is blended for
temperatures above 0°F (−18°C).
It is important that diesel-powered trucks are
refueled only with ultra low-sulfur fuel. The
emission control system requires the use of diesel
fuel with ultra low-sulfur (0.0015% by weight, or
15 ppm, maximum) content. Both ultra low-sulfur
and higher sulfur diesel fuels are available in
the United States. Use of fuels with higher-sulfur
content will affect the function of the emission
components and may cause reduced performance,
excessive smoke, and unpleasant odor.
At a minimum, the diesel fuel you use should
meet the latest version of specification
CAN/CGSB-3.517 (Low Sulfur Diesel) in Canada.
In addition, the Engine Manufacturers Association
(EMA) has identified properties of an improved
diesel fuel for better engine performance and
durability (FQP-1A). Diesel fuels corresponding tothe EMA description could provide better starting,
less noise, and better vehicle performance. If
there are questions about the fuel you are using,
contact your fuel supplier.
If your vehicle has the 6.6L engine, it is acceptable
to use diesel fuel containing up to 5% biodiesel
(B5), but the final blended fuel must meet the same
specification, CAN/CGSB-3.517 (Low Sulfur Diesel)
in Canada, as other fuels used in your vehicle, and
the biodiesel used for making this fuel must meet
the latest version of ASTM specification D 6751.
Biodiesel is produced from vegetable oils or animal
fat that have been chemically modified to reduce
the possibility of damage to your fuel system and
engine. Higher concentration (i.e., greater than B5)
biodiesel-containing fuels or the use of unmodified
bio-oils blended into diesel fuel at any concentration
is not recommended and could damage your fuel
system and engine. Such damage would not be
covered by your warranty. If there are questions
about the biodiesel-containing fuels you are using,
contact your fuel supplier.
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Very Cold Weather Operation
Follow the instructions listed previously under the
heading “What Fuel to Use.”
Notice:Never use home heating oil or
gasoline in your diesel engine. They can cause
engine damage.
In cold weather, your fuel filter may become
clogged (waxed). To unclog it, move the vehicle to
a warm garage area and warm the filter to
between 32°F and 50°F (0°C to 10°C). You will
not need to replace it. Additional information on the
fuel filter follows.
Water in Fuel
{CAUTION:
Diesel fuel containing water is still
ammable. You could be burned. If you
ever try to drain water from your fuel,
keep sparks, ames and smoking
materials away from the mixture.Notice:If there is water in your diesel fuel
and the weather is warm or humid, fungus and
bacteria can grow in the fuel. They can
damage your fuel system. A diesel fuel biocide
can be used to sterilize your fuel system.
However, your fuel system may still need to be
cleaned. Your dealer can advise you of the
appropriate solution.
If your fuel tank needs to be purged to remove
water, see your dealer or a quali ed technician.
Improper purging can damage your fuel system.
Sometimes, water can be pumped into your fuel
tank along with your diesel fuel. This can happen if
a service station does not regularly inspect and
clean its fuel tanks, or if it gets contaminated fuel
from its suppliers.
If this happens, the
water-in-fuel light, if
equipped, will come on
in the instrument panel.
If it does, the water must
be drained. Your dealer
can show you how to
do this.
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4. Open the drain
valve by turning
two to three turns.
When fuel empties
from the valve,
all the water
has been drained.
Close the valve
hand-tight.
5. Remove the fuel-resistant container and
properly dispose of the contaminated fuel.
To find out how to properly dispose of
contaminated diesel fuel, seeEngine Oil
(Caterpillar
®Diesel Engine) on page 268or
Engine Oil (Gasoline Engine) on page 268or
Engine Oil (DURAMAX
®/Isuzu Diesel
Engine) on page 272.6. Install the fuel cap.
7. Start the engine and let it run for a few
minutes. If the engine stalls, the fuel system
may need to be primed. While draining
the water from the fuel filter, air may enter the
fuel system. If air has entered the fuel
system the fuel system will need to be primed.
If the water-in-fuel light comes on again after
driving a short distance or the engine runs rough
or stalls, a large amount of water has probably
been pumped into the fuel tank. The fuel
tank should be purged.
Fuel Priming
If your vehicle has a Caterpillar®diesel engine,
see the Caterpillar®Diesel Engine Operation and
Maintenance Manual provided with your vehicle.
If your vehicle has a DURAMAX
®/Isuzu diesel
engine, in order for the fuel system to work
properly, the fuel lines must be full of fuel and
contain no air. If air gets into the fuel lines, it will
be necessary to prime the fuel lines to eliminate air
before operating the vehicle.
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Priming the 7.8L Isuzu 6H Diesel Engine
If your vehicle is equipped with the 7.8L Isuzu 6H
diesel engine, use the following procedure to
prime the engine:
1. Make sure there is fuel in the fuel tank.
2. Make sure the specified fuel filter is properly
installed.
3. Make sure the fuel lines are securely
connected.
4. Make sure the fuel filter is cool to the touch.
5. Use a clean cloth to remove dirt and oil
from the fuel filter head and breather valve.6. Use the palm of your hand to repeatedly
press and release the plunger (1) at the
top of the fuel filter priming pump. Continue
until the plunger resistance becomes firm. This
may take from 20 to 100 times, depending
upon fuel tank location.
7. Turn the fuel filter breather valve screw (2)
counterclockwise several turns to open the
breather valve.
8. Use the palm of your hand to repeatedly
press and release the plunger (1) at the
top of the fuel filter priming pump until fuel
begins to seep from the breather valve.
9. Tighten the fuel filter breather screw (2) to the
specified torque, 4.9
Y(43 in. lbs).
10. Use the palm of your hand to press and
release the plunger (1) at the top of the
fuel filter priming pump about 20 more times.
This sends fuel to the engine.
11. Use a clean cloth to remove any fuel from the
fuel filter and surrounding area.
12. Start the engine and allow it to idle for a
few minutes.
13. Check the fuel filter for leakage.
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