GMC TopKick 2007 Owner's Manual page 255

Fuel Priming
If your vehicle has a Caterpillar
®
see the Caterpillar Diesel Engine Operation and
Maintenance Manual provided with your vehicle.
If your vehicle has a DURAMAX
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.
Air can get into the fuel lines if any of the following
happen:
•
The vehicle runs out of fuel.
•
The fuel filter is removed for servicing or
replacement.
•
The fuel lines are removed or disconnected
for servicing.
•
The fuel filter water drain valve is opened
while the engine is running.
®
diesel engine,
®
/Isuzu diesel
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
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.
®
Diesel
255