In practical terms. If the car is on the flat or nose down hill, just filling the filter right to the top has worked for me for the last 30 years.
If you have a weak primary pump, have the car facing up hill, dont fill the filter right up, have air leaks, have a non standard fuel system, leave the filter off for an extended period, have a weak battery or are using something other than diesel you will have problems and will need to bleed the system.

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Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving