Make sure the fuel tank breather isn't clogged by loosening your fuel cap and listening for suction. If you hear air woosh in, your tank has become a vacuum chamber and you won't get any fuel if the lift pump can't overcome it.
You may also want to check every rubber seal and hose from the tank to the lift pump, to the filter to the IP and back to the filter. Running WVO or bio can and will destroy all the rubber seals and you can be sucking in air this way or bleeding out fuel pressure at the top of the IP if the delivery valve seals are done. It's good practice to do anyway regardless what you run, WVO, bio, or even plain diesel.
Phil Forrest

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1972 220D "Trudy," named by a friend.

"The 220D sounds good... I suspect it is the only car that you need a calendar for, rather than a stopwatch, when doing acceleration tests."
Tom Abrahamsson