Chevrolet T-Series Owner's Manual page 182

Fuel Priming
In order for the diesel engine 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.
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.
182
For vehicles with cruise control, you can prime the
vehicle and remove the air from the fuel system.
The following procedure will show you how:
1. Make sure there is fuel in the fuel tank.
2. Make sure the specified fuel filter is properly
installed.