Sounds like a bad monovalve. Take it out, remove the 4 scws at the top and pull out the solenoid/diaphragm assy and see if the rubber is broken. If so, a $20 part will fix it to new.

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1984 300D Turbo - 4-speed manual conversion, mid-level resto

1983 300D - parts car

1979 300TD Auto - Parts car.

1985 300D Auto - Wrecked/Parts.


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"If you don't know where you are going, any road will get you there". Lewis Carrol