Oil filter filling

[RPGR90s]

I've just seen some solid evidence that pre-filling a new oil filter measurably reduces particles compared to a dry filter at start up.

Our airhead filters slide in sideways makes pre-filling impossible.

I would like to know if you soak your filters before insertion.

Or?

In all honesty, I think you're over-thinking this. Like others have said, I install a dry filter (1974 R90s), and spin the engine without starting to see the oil pressure light go out. And then start normally.

[Rob Frankham]

I've just seen some solid evidence that pre-filling a new oil filter measurably reduces particles compared to a dry filter at start up.

Our airhead filters slide in sideways makes pre-filling impossible.

I would like to know if you soak your filters before insertion.

Or?

Hmmm, I've had the chance to watch that video through and I have to say that I don't give it a lot of credence. The presenters don't seem to be able to decide whether they are talking about bearing damage due to oil born particles or due to low oil pressure and their fantastic reveal towards the end of the video is more or less pointless, not because the conclusion is wrong but because it simply states what anyone with a brain would expect in those circumstances. In essence, they compare the particle count of oil direct from the drum with the count from oil drawn from the sump after it has been circulated through the engine. Bear in mind that:

1) The oil has been put into a sump that already contains a residue of 'dirty' oil.

2) It has been pumped through the engine via galleries that also contain a quantity of 'dirty' oil.

3) The second sample is drawn from the sump plug which is deliberately located at the bottom most point of the sump so that drawing off the oil will tend to carry out much of the layer of sludge that accumulates there.

So... you take clean oil, put it into a dirty engine and then make a song and dance about ir being dirtier than when it went in... really?

What would have been an interesting test (although perhaps not in the context of this video) would be to take samples a) from the barrel, b) from the sump before the oil is criculated, c) from the gallery immediately after the filter and d) from the sump after the oil has circulated. This would give an indication of exactly where the contamination is coming from.

There are so many anomalies in the video, I'm not going to even try to go through them all... the bottom line is:

Particulates are carried through the engine by the oil.

Following an oil change, all of the oil except that which is still in the galleries (i.e. the residuum of the old oil) goes throught the filter. It is an acceptable theory (although not proven and not addressed in the video under consideration)that the filter works best when it is soaked in oil but as soon as the oil reaches it, it is soaked in oil so we can say that the filter will take out all of the particulates, or at least most... nothing is perfect.

I can agree that it is reasonable to think that the length of time between the engine starting to turn and the oil pressure reaching it's normal value might lead to metal to metal contact... but this doesn't appear to be the experience in the industry. What can be said is that there is still oil on the bearings and there is still oil (albeit old pre-change oil) in the system before the new oil comes through. It would certainly be a mistake to run the engine hard before the pressure is up but cranking and idling is fairly safe. Priming the system before starting is even safer.

If you feel better filling a canister filter with new oil then by all means do so, it won't do any harm.

If you want to soak your cartridge, by all means do so (if you can put up with the mess)... it won't do any harm.

If you want to spin your motor, plugs out until the light goes out, by all means do so (I do as a matter of course). Certainly a good idea when the engine is just rebuilt as there is a lot more oil space to fill.

Do any of these things make a big difference... probably not.

Rob

[jackonz]

I have never heard such utter codswallop re filling an oil filter with oil prior to fitting, am now 71 and I have been in the motor industry since I was 18 so I have a few years experience in this with 20 of them in engine reconditioning.
Whenever possible I have always pre filled the filter with oil prior to installation on the engine it has never been an issue, in fact we used to pressure prime engines with oil before we shipped them to customer, so why fill the filter with oil is simple you will get oil pressure up quicker and that is good for your engine.
What I and many of us do not like is some manufactures have removed the drain plug from the sump on engines forcing you back to the dealer for oil changes.
As for the airhead filter well you could soak it in oil but I doubt it would make much difference as your not filling the cavity where the filter is housed, just start it up and don't rev it hard, there are cars out there with similar issues as in the Mk4 2ltr Golf engine the filter is upside down from the conventional so if you filled it with oil it will spill all over the place when you try to fit it.

[mkj]

With my car I remove the fuel pump fuse so I can build up the oil pressure after a filter change