Its normal. As soon as it warms up the nocking goes away. Sounds like you own a FORD

Its normal. As soon as it warms up the nocking goes away. Sounds like you own a FORD - 1

Hydraulic valve lifters sometimes take a few seconds (or minutes) to fill with oil.

This is not restricted to any one make.

Yes

HI so the knocking is lack of oil pressure due to the tolerances becoming bigger due to wear of major parts of the engine mains bearings, crankshaft bearings where oil leaks out the sides of the shell bearing so fast no pressure builds up. In other words a knackered engine.