Only a used car sales person could say that with a straight face.

Basic list to check:
#1. Go get a couple gallons of diesel and add to fuel tank = fuel gauge may be wrong = empty tank.
#2. Remove screw on filter, check O ring on bolt and replace if damaged, fill filter before installing, tighten filter very hard with wrench, then prime for fifteen minutes.
#3. Replace rubber hoses from lift pump to body.

Note:
If primer pump is leaking fuel while pumping = bad pump, replace it.

__________________
ASE Master Mechanic

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Vehicle build.
Fleet Durability
Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D

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