A 1 .
Be sure to keep the line clear of
moving engine parts (fan, pulleys, etc.)
and DO NOT place the line on the
Replace fuel lines (para. 3-26).
Check the filter vent screw for tightness.
Check the supply lines for kinks, cracks. leaks, or loose
connections that could restrict fuel flow or allow air to enter the
Remember that under certain operating conditions parts
of the fuel system can be under vacuum so that loose connections
that may not leak fuel can let air in.
To test for air leaks in the supply lines, disconnect the return line
from the injection pump and connect a line that is long enough to
reach the ground.
Place the end of the line into a bucket
containing diesel fuel, making sure that the end of the line is below
the level of fuel in the bucket.
Run the engine and watch for air
bubbles in the bucket. You can also replace the short return line
from the injector pump with a clear piece of tubing to check for
Inspect the return lines for kinks or any other
that may restrict fuel flow.
Inspect fuel return check valve for any
restrictions (para. 3-36).
Replace fuel line (para. 3-26).