While this video about Cat Diesel oil and petrol filters, the principles are the same for the oil filters on our petrol driven vehicles and it does raise some interesting questions. If we are filling via the large spin on hole on filter we are filling at the outlet side and are probably doing very little in terms of priming the oil pump or oil lines. Also, while new oil is hopefully clean and free of debris, if there is a foil cap on the oil pack that fully or partially falls off, or anything else in the oil that shouldn't be, it's going to go into the engine without being filtered. Even if we keep filling the filters at the outlet hole as the level subsides it is probably just being soaked up by the filter media in a sponge like fashion rather than passing to the filter inlet side. So do we pre-fill and if so should we be doing it with a small funnel one of small perimeter inlet holes using a suitable small funnel? I suspect we should fill from both a perimeter hole and large outlet hole just so we get oil on the inlet pump side and also reduce the amount of oil we have to add after first post oil fill start up.

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FF to 7:59

I've never prefilled my oil filter and never had a problem. I just make sure to wipe a little clean oil on the rubber o-ring before spinning the filter on. Hopefully that helps to seal it.

My car doesn't have an oil burning diesel engine in it though