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3. Remove the rubber
cap from the rear of
the chamber.
4. Put the release stud, nut and flat washer into the
chamber.
5. Turn the stud clockwise a quarter of a turn.6. Turn the stud nut
clockwise several turns
to release the brakes.
Follow the same
procedure to release
the other brake or
brakes.
7. At the repair facility, apply air pressure of at least
70 psi (480 kPa) to the brake chambers, either
from an external air supply or the vehicle’s
air system.
8. Turn the stud nut counterclockwise several turns.
Remove the stud from the chamber.
9. Replace the stud and washer and tighten the nut
into the side of the chamber.
10. Replace the rubber cap.
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If one or more of the above occurred, it is very likely
that air has entered your fuel system and that you will
need to prime the fuel system before operating the
vehicle.
Air in the fuel lines will not harm the engine or the
vehicle. However, the engine may not be able to start
until the fuel system is primed and the air is removed.
Priming the 6.6L DURAMAX®Diesel
Engine
If your vehicle is equipped with the 6.6L DURAMAX®
diesel engine, it has a priming pump which is part of the
engine mounted fuel filter. The vent valve and the fuel
filter primer pump are located on top of the fuel filter
housing. The priming pump is hand operated and is
designed to bring fuel to the engine to eliminate any air
that may be in the fuel lines.
To prime the 6.6L DURAMAX
®diesel engine, do the
following:
1. Make sure there is fuel in the tank.
2. Make sure the fuel filter had been installed and
properly tightened.3. Make sure the fuel lines are properly connected
and the fuel filter is cool enough to touch.
4. Remove any dirt from the fuel filter head and vent
valve by wiping with a cloth.
5. Open the fuel filter vent
valve by turning the
screw counterclockwise
several full turns.
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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 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
counterclockwise several turns to open the breather
valve.
8. Use the palm of your hand to repeatedly press and
release the plunger 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 to the specified
torque, 4.9Y(43 lbs in).
10. Use the palm of your hand to press and release the
plunger 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.Running Out of Fuel
If the diesel engine stalls and you think that you have
run out of fuel, do this to restart your engine:
{CAUTION:
Diesel fuel is ammable. It could start a re if
it gets on hot engine parts. You could be
burned. Do not let too much fuel ow from the
air bleed valve, and wipe up any spilled fuel
with a cloth.
1. If you are parked on a level surface, add at least
2 gallons (7.6 liters) of fuel. However, if you are
parked on a slope, you may need to add up to
5 gallons (18.9 liters) of fuel.
2. Follow the fuel priming procedure earlier in this
section to prime the fuel filter.
3. Close the air bleed valve.
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5. Reinstall and tighten the filter container and
reconnect the water sensor wire to the filter.
6. Use the fuel filter priming procedure earlier in this
section to prime the fuel filter.
7. Tighten the air bleed valve by turning it clockwise
until hand-tight.
8. Start your engine and let it idle for five minutes.
Check your fuel filter and air bleed valve for
leaks.
How to Reset Fuel Filter Change
Light - DURAMAX®6.6L (LMM) Engine
The engine controller calculates when to change
the fuel filter based on vehicle and fuel use. Anytime
your fuel filter is changed, reset the fuel filter light so the
engine controller can calculate when the next fuel filter
change is required. If a situation occurs where you
change your fuel filter prior to a change fuel filter light
being turned on, reset the fuel filter change light.To reset the Fuel Filter Change light:
1. Turn the ignition key to RUN with the engine off
2. Fully press the accelerator and brake pedals at the
same time for 10 seconds. If the Fuel Filter Change
light flashes for 5 seconds, the system is resetting.
3. Turn the key to OFF
If the Fuel Filter Change light comes back on when you
start your vehicle, the light has not been reset. Repeat
the procedure. SeeChange Fuel Filter Warning Light on
page 3-44for more information.Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel might be hard
to find. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel. Costly
repairs caused by use of improper fuel would not be
covered by your warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you will be driving.
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