Duramax Diesel. Manual - part 14

Driving and Operating

4-Cylinder Pickup

2. Place a container under the

filter drain valve. The filter drain
valve is on the bottom of the
fuel filter. The filter drain valve
is under the vehicle on the
driver side, inside the
frame rail.

3. For 8-cylinder pickup and

4-cylinder van models, open
the drain valve by turning it
counterclockwise. Allow the
filter to drain until all of the
water has been removed.
Close the valve.

For 4-cylinder pickups, open
the fuel filter drain valve by
turning it two to three turns.
Allow the filter to drain until all
of the water has been
removed. Close the valve hand
tight.

4. Properly dispose of the water

contaminated fuel.

5. Start the engine and let it run

for a few minutes. During the
draining process, air may have
entered the fuel system. If the
engine stalls, the fuel system
may need to be primed. See
“Fuel Priming” following.

Fuel Priming

For the fuel system to work properly,
the fuel lines must be full of fuel.
If air gets in, the fuel lines need to
be primed before operating the
vehicle and the fuel operated
heater (FOH).

If air is present, the following may
have happened:
.

The vehicle ran out of fuel.

The fuel filter was removed.

The fuel lines were removed or
disconnected.

The fuel filter water drain valve
was opened while the engine
was running.

The FOH pump and FOH fuel
lines were removed or
disconnected.

The system is not harmed by air in
the fuel lines; however, the engine
and/or the FOH may not start until
the fuel system is primed and the air
is removed.

Priming the Fuel System

There is an electric priming pump
that will bring fuel to the engine and
eliminate air in the fuel lines. To
prime the engine:

1. Correct any condition that

caused the loss of prime.

2. Turn the ignition to ON/RUN for

30 seconds. Do not start the
engine. The fuel pump will start
priming.

3. Turn the ignition off, then back

to start, and crank the engine
for 15 seconds.

Driving and Operating

4. If the engine does not start,

repeat Steps 2 and 3 until the
engine starts.

If the engine does not start
after repeating Steps 2 and 3
three times, turn the ignition
key off for 60 seconds.

5. Repeat the above steps until

the engine starts.

6. If the engine starts, but does

not run smoothly, increase the
engine speed slightly.

7. If the engine starts and runs

but stalls again, turn the
ignition off for 60 seconds.

8. When the engine starts, let it

idle for a few minutes and
check the filter for any leaks.

To Prime the Fuel Operated Heater
(FOH) Fuel Lines (Van Models)

See your dealer or qualified
technician if the FOH fuel lines need
to be primed.

Running Out of Fuel

8-Cylinder Pickup Models

{

Warning

Diesel fuel is combustible. It could
start a fire if it gets on hot engine
parts. You could be burned. Catch
any fuel from the air bleed valve,
and wipe up any spilled fuel with
a cloth.

If the engine has stalled due to
running out of fuel, try the following
steps to restart it:

1. If parked on a level surface,

add at least 7.6 L (2 gal) of
fuel. Up to 18.9 L (5 gal) may
be needed if parked on a
slope.

2. Follow the fuel priming

procedure earlier in this section
to prime the fuel filter.

3. Turn the ignition key to START

for 10 to 15 seconds at a time
until the engine starts. If the
engine tries to run, but does

not run smoothly, increase the
rpm slightly by using the
accelerator pedal. This will help
force air through the system.

4. Return to Step 2 if the engine

stalls and will not restart.

5. After a few attempts, if the

engine still does not start, see
your dealer.

4-Cylinder Pickup and Van
Models

If the engine has stalled due to
running out of fuel, try to restart it:

1. If parked on a level surface,

add at least 3.8 L (1 gal) of fuel.
Up to 18.9 L (5 gal) may be
needed if parked on a slope.

2. Follow the vehicle fuel system

priming procedure earlier in
this section to re-prime the
system and restart the engine.

If the check engine light comes on
due to running out of fuel, it may
take a few drive cycles to clear.

On van models only, the fuel
operated heater (FOH) stops
automatically when the fuel tank

Driving and Operating

volume is less than or equal to 10%
of the total tank. The FOH fuel lines
will not need to be primed if the
vehicle runs out of fuel.

Fuel Filter Replacement

8-Cylinder Pickup and 4-Cylinder
Van Models

{

Warning

Diesel fuel is flammable. It could
start a fire if something ignites it,
and people could be burned. Do
not let it get on hot engine parts,
and keep matches or other
ignition sources away.

The fuel filter is on the driver side,
inside the frame rail.

To replace the fuel filter:

1. Drain any water from the filter.

See “Removing Water from the
Fuel Filter” in Water in Fuel
0 52.

Keep the engine off until the
procedure is completed.

2. Apply the parking brake.

Van Shown, Pickup Similar

3. Remove the filter element cap

by turning it counterclockwise.

4. Remove the filter element.

If there is any dirt on the filter
sealing surface, clean it off.

5. Install the new filter element

and o-ring.

6. Reinstall and tighten the filter

cap to the housing.

7. Use the fuel filter priming

procedure to prime the fuel
filter. See “Fuel Priming” in
Water in Fuel 0 52.

8. Start the engine and let it idle

for five minutes. Check the fuel
filter and air bleed valve for
leaks.

9. Reset the fuel filter monitor.

See Driver Information Center
(DIC) 0 21.

If the van Fuel Operated Heater
(FOH) (if equipped) is not working,
the FOH line requires priming. See
your dealer for service. See Fuel
Operated Heater (FOH) (Van
Models Only) 0 38.

4-Cylinder Pickup Models

{

Warning

Diesel fuel is flammable. It could
start a fire if something ignites it,
and people could be burned. Do
not let it get on hot engine parts,
and keep matches or other
ignition sources away.

Driving and Operating

The fuel filter is on the driver side,
inside the frame rail in front of the
fuel tank.

1. Drain any water from the filter.

See “Removing Water from the
Fuel Filter” in Water in Fuel
0 52.

Keep the engine off until the
procedure is completed.

2. Apply the parking brake.

3. There are two caps under the

filter. Clean the fuel filter area
before removing these two
filter caps.

Caution

Failure to cover the fuel filter with
a clean cloth to keep out debris
when replacing may cause dirt to
get into the engine. This could
cause engine damage. Keep the
fuel filter covered with a clean
cloth when replacing.

4. Remove both filter elements.

If there is any dirt on the filter
sealing surface, clean it off.

5. Install the new filter elements

and tighten both caps.

6. Use the fuel filter priming

procedure earlier in this section
to prime the fuel filter.

7. Start the engine and let it idle

for five minutes. Check the fuel
filter for leaks.

8. Reset the fuel filter monitor.

See Driver Information Center
(DIC) 0 21.

Filling the Tank

{

Warning

Fuel vapors and fuel fires burn
violently and can cause injury or
death.

To help avoid injuries to you
and others, read and follow
all the instructions on the
fuel pump island.

Turn off the engine when
refueling.

Keep sparks, flames, and
smoking materials away
from fuel.

(Continued)

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