Prefilling Oil Filters - Necessary?

I see no proven harm in doing this, if you can. Physics is physics, if the can is empty, it takes longer to build pressure on the output side. I have found that many ADBV's don't hold oil for very long on inverted filters (open side down), no matter how much they cost.
 
When it comes to prefilling filters, I guess it all depends on who you listen to.
A dozen+ years ago, I read the TSB from Caterpillar that says not to prefill their oil filters. Too many Cat field techs were probably just putting old, dirty oil back into the replacement filter, I guess. Fast forward to about a week ago, I was changing oil on a neighbor's CaseIH 8830 farm hay swather. (Most city folk will have to do a search on what that machine actually does)
Anyway, this is the filter that I took off of the machine. The photo is a little fuzzy, but the diagram on the filter shows that you 1. Add oil to the filter. 2. Put oil on the base gasket. 3. Spin it until the gasket contacts the engine. 4. Tighten it another 3/4 turn. This filter is not a huge filter, either, so it shouldn't take too long to fill on its own. It's probably about the size of a Fram PH8A.
The new filter that I installed was a factory CNH replacement.
 

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The problem with pre-filling filters is idiocracy. Sorry, many morons do a horrible job of removing the aluminum/plastic seal on jugs/bottles and that seal ends up in the filter, and on the wrong side of the filter. Pulled plenty of seals, funnel tips, and bottle caps/rings from under valve covers and expect the same inside filters. My favorite foolishness are destroyed engines caused by funnels breaking the PCV baffles/shields off under the valve/rocker cover. If you can't fill an engine correctly without problems, should you be filling your filter?

I prefill all my filters regardless of mounting location. On sideways or upside down filters, I can still pre-fill and soak the media without spilling a drop during installation. And, I prefill cartridges too.

So, if you are not a moron, then prefill your filter. If you are not capable of filling the filter without debris, maybe you shouldn't be doing your own oil changes. I mean, if you can't remove the plastic/aluminum seal, or the plastic cap/ring, off of a jug or bottle of oil, or use a funnel properly, stick with jippylube!

Funnel companies have 'vehicle specific' funnels now too. Oil bottling companies need to idiot proof oil bottle seals and cap rings.

I would also not recommend pre-filling a filer during a sand storm 🤣 That would be uncommon sense.

I don't care if you do or don't and if you think that its fine to do or not to do.

Btw, I won't start a new/rebuilt engine without priming the oil system too.

Maybe you don't trust these clowns masquerading as an engine company... but this is what they say:

The problem with these fancy funnels, in the hands of DIY clowns, is that many don't have a 'screen' to catch foolishness:

Even a Behrens, older than most members here, has a screen:

And, what ever iffylube or indie shop should be using:
 

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I've never done it, and haven't seen the need. My oil pressure gauges over many vehicles are happy within 1 to 2 seconds after start. If that 1 to 2 seconds is an issue, then God help us that have American-built SUV's and trucks that last 250,000 to 300,000 miles doing it the "dry way."

This thread has been so unfulfilling... ;)
 
I've never done it, and haven't seen the need. My oil pressure gauges over many vehicles are happy within 1 to 2 seconds after start. If that 1 to 2 seconds is an issue, then God help us that have American-built SUV's and trucks that last 250,000 to 300,000 miles doing it the "dry way."

This thread has been so unfulfilling... ;)
It’s just overdue for a sidetrack 😷
 
The Cummins site Greasymechtech linked to recommends prefilling the oil filter. Wow, did no know any engine company recommended prefilling.

I used to prefill for many years, stopped prefilling for the last few years, based on that residual warm oil in the bearings will provide adequate lubrication for a few seconds while the filter fills up. I have a lot of respect for Cummins, now I might go back to prefilling.

Not sure why Greasymechtech is dissing Cummins, they have the lions share of the HD engine market in North America. Even top tier truck manufacturers Peterbilt and Kenworth, use Cummins based engines.
 
Wut ? You don’t ? 😷
i had an oil gauge fluctuation on a mechanical gauge that drove me crazy so i took off the old copper tubing and put on about three feet of coiled nylon. worked like a charm, my oil pressure is rock steady now 🤣
 
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Sarcasm and not dissing

I prefilled and Cummins says to. Dont need to believe me at all. But, I think some should believe Cummins. Yes, lions share!
 
I might remember to prefill with some oil when installing large, vertically mounted, thread-upwards, canister filters like Motorcraft FL500 or FL1995.

If I forget I don't really lose any sleep. Usually the engine is warm, oil is still in the journals. and the pump volume is high enough to supply consistent oil flow within a second or two anyway.

Its a mute point in my opinion. Half the engines in cars I've owned had cartridges on top of the engine that 1) you cant prefill and 2) probably take s longer to fill with oil flow. 3) I can't remember any owners manual in recent memory making this a big deal one way or the other .
 
If making sure the oil gets to where it needs in as little time as possible, actually makes any meaningful difference to engine life, then why don't vehicles come with some sort of pre-ignition oil priming with an electric oil pump? I know there are aftermarket systems for this, but I can't imagine it would be difficult at all to design an OEM electric pump that primes the oil before starting. Sure, the ADBV might still be helpful to keep contaminants from back-flowing out of the filter media, but oil would be right where it needs to be every start, even after an oil change and new, empty filter. And it's not like the priming oil pump needs high flow or crazy PSI.

Or, maybe the ones who engineer these engines know that the dry start for oil changes is hardly a drop in the bucket in terms of all the things that cause an engine to wear out?
 
It would, but the dirty oil in sump would go through the filter media before going into the engine. Cat's theory was that the new oil was contaminated enough (maybe bulk oil in dirty storage containers?) to cause engine damage if the filter was pre-filled, which means dirty oil going into the engine before being filtered.
A Cummins engine was denied warranty on a piston seized due to a sliver of foil that blocked a very fine oil passage. A Cat oil filter on the instruction labeled on the can states do not pre fill filter. There are some videos on how to pre fill the filter by not pouring the oil in the center hole. Personally I put the accelerator to the floor and crank the engine over for a 5 count. I do this when the car is sitting for a while too just to get the oil lines filled.

As clean looking as brand new oil looks you still are trusting the oil manufacturer did not put a booger in there. Maybe the booger floats?
 
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A Cummins engine was denied warranty on a piston seized due to a sliver of foil that blocked a very fine oil passage. A Cat oil filter on the instruction labeled on the can states do not pre fill filter. There are some videos on how to pre fill the filter by not pouring the oil in the center hole. Personally I put the accelerator to the floor and crank the engine over for a 5 count. I do this when the car is sitting for a while too just to get the oil lines filled.

As clean looking as brand new oil looks you still are trusting the oil manufacturer did not put a booger in there. Maybe the booger floats?
There is probably a 99.9% chance a sliver of foil went into the engine from the person taking the foil off and pouring the oil. Not from the oil as received from the oil company. The Cat statement I read also stated upon their examination with a microscope material in new oil appeared organic. Well yeah, oil attracts floating lint and dust in the air like a son of a gun anytime the oil isn’t covered, like when pouring it. Lint and plant material is everywhere, especially in an oil funnel.
 
Just crank the engine over a few times before starting. How hard is that, many engines have full throttle no start and/or take the ignition fuse out. Plug leads off for the old school engines.
 
I see no harm in doing it but I also think its a waist of time doing it, that filter is full of oil in seconds after you start that engine plus there's residual oil still in the bearings and on the crank, etc. I never pre fill in 30+ years of oil changes.
 
Just crank the engine over a few times before starting. How hard is that, many engines have full throttle no start and/or take the ignition fuse out. Plug leads off for the old school engines.

If you're going to crank a modern engine over, you might as well leave the ignition plugged in and just start it, you'd be doing the same startup damage whether or not the ignition is plugged in because the rotating assembly is spinning

With engines equipped with a distributor, you could prime the engine by spinning the oil pump drive gear and not spin the rest of the rotating assembly.
 
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