Remove the vacuum line from the white plastic shutoff box (top of injection pump).

Try starting, if it starts, the ignition vacuum valve (attached to steering column lock) has failed = holding vacuum on it at all times.

If it fails to start, it should be one of the following issues.
* If you filled the fuel tank today, possible BAD fuel. 2 stroke oil and/or Diesel911 may cure this.
* Plugged filters. Bad fuel or infestation..
* Massive air leak into the fuel system. The fuel thermostat plastic end O-ring leaking is a common issue.
* Massive vacuum in the fuel tank. A bad vent valve will do this, remove the filler cap and try starting.
* Lift pump failure. Test output volume.
* Injection pump solenoid failure. Hope it is not this, (no longer available) find a good used unit.


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__________________
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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