Hello BenzDiesel
Suggest:
Unbolt lift pump, leave lines connected, use large channel locks to depress plunger twenty or thirty times, look for plunger leak, listen for squeak of fuel bypass, remount lift pump.
disconnect injector bypass hose from fuel filter housing, cap fuel filter housing fitting, watch for fuel from the bypass hose and crank engine.
Remove or disconnect the TRAP and try starting.

__________________
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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