Bob Rooks

An eighth of 7 gallons isn't very much. Put another two gallons in it.

Because the sediment bowl is full, doesn't mean a thing. Even if you run out of fuel there will still be fuel in it. The lift pump takes it's suction from the TOP of the bowl. Are you reluctant to remove the sediment bowl and check the screen in the top? Do you have concerns about removing the sediment bowl assembly to see if you have a plugged in-tank screen? If it turns out you have diesel bugs you are going to have to do some serious tank cleaning, and treat your fuel with a biocide. If you have a stationary fuel storage tank, you will have to clean and treat that too. The bugs are corrosive and can ruin a fuel injection pump and all the injectors.

Hopefully you saw the guy on TBN that had a Chinese tractor wrecking yard. I see his post is gone now.

Cranking the engine with the line disconnected that goes to the filter won't be an accurate indicator of volume produced by the pump. It may pump some fuel but if there is a suction restriction it won't tell you that.

Ok, there's some oil in the injection pump, that's good.

You should get a good gravity flow of fuel from the tank. Did you check the sediment bowl screen? You have to remove the bowl, the screen is located above the gasket. Did you drain the tank and remove the sediment bowl/shutoff valve assembly to see if there is an in-tank screen? Don't rely on just a trickle of fuel to determine there is no restrictions. You won't get any fuel flow downstream of the lift pump because it contains two spring loaded check valves – if you do, then that means the check valves aren't holding and the lift pump is defective. A defective lift pump will give the same symptoms as “sucking air”.

I understand that on some models there is a screen inside the tank attached to the sediment bowl. There is also a very fine screen in the sediment bowl itself. Hope you don’t have bugs. See if have a dark sludge anywhere.