1981 Mercedes Benz 300sd cranks but won't start

1981 MERCEDES BENZ 300SD
200,000 MILES • 4 CYL • 2WD • AUTOMATIC
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HIPPSAKAMO
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I purged the lined with the plunger, no effect. I have noticed that if a disconnect the fuel line in, rifgt at the plastic fuel pre-filter, no fuel is pumped. I do not hear the fuel pump with the key on or when the car cranks. Shoud I hear it? Fuel does seem to pump out of the injector pump though. I suspect the fuel pump. Am i missing anything?
Aug 22, 2009 at 6:15 AM
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JACOBANDNICKOLAS
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It does sound like the fuel pump is weak or bad. Here is a how to for checking it. Check it out and let me know what you find.

https://www.2carpros.com/how_to/how_to_check_fuel_pressure.htm
Aug 22, 2009 at 9:28 PM
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HIPPSAKAMO
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thanks, where is the fuel pump? CHILTON SAYS IT IS IN LINE, under the left pass floor panal, but I DON'T see it there. is it in the fuel tank? in line next to the fuel tank?
Aug 23, 2009 at 6:20 PM
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JACOBANDNICKOLAS
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I just tried liiking i up with our online repair manual and the info isn't available. I believe the Chilton manual is correct. I don't think it's in the tank on your model.
Aug 24, 2009 at 3:00 PM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.