Wow. So many replys for something sooooooo unimportant...
Never Prefill oil filters!
- Thread starter Vern_in_IL
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I've already stated what I do, so won't repeat that.
I'd say using the, enough engine oil film at start up without prefill as argument, taken to it's logical conclusion would also mean that adbvs in oil filters are completely unnecessary. That true, oil filter companies wasting a lot of money including them.
Also bits of foil from container seal just as likely to be dumped down the fill hole with an OC as with prefilling the filter. So, being non observant or unlucky at any point in the OC can be a hazard.
Still difficult for me to accept that 100% of same new oil dumped down the fill hole never touches any bearings surface before going through the oil filter.
I'd say using the, enough engine oil film at start up without prefill as argument, taken to it's logical conclusion would also mean that adbvs in oil filters are completely unnecessary. That true, oil filter companies wasting a lot of money including them.
Also bits of foil from container seal just as likely to be dumped down the fill hole with an OC as with prefilling the filter. So, being non observant or unlucky at any point in the OC can be a hazard.
Still difficult for me to accept that 100% of same new oil dumped down the fill hole never touches any bearings surface before going through the oil filter.
Originally Posted by Shannow
More BITOG gold....
Facts
* new oil can be very very dirty
* prefilling put the new oil on the engine side of the rock trap
* bypass is closed when the filter is passing air to pre-fill the engine
* the dirty oil that you are emptying into the engine gets to go through the filter first before the bearings
* even at that point IF the filter is in bypass, then some/most of the oil gets through the media.
* prefilling gives you more chance of dropping something bigger down the hole, which another poster has identified with bits of foil.
* there is no metal to metal contact on that start, as there's plenty of oil and tribofilm left from when the engine was running.
Another fact is that I have never seen an automotive maintenance document produced by an OEM that tells one to prefill a filter...would be very interested in seeing one, to make it my first.
Of COURSE manuals telling you not to prefill are not common (the big diesel example cited excepted), as telling you to not to do something that you wouldn't normally do is superfluous:
* don't add coolant to windshield washer fluid
* don't use icepick to clear windscreen.
Maybe we should all make remote filter mount pump setups with screw on 2 micron hydraulic filters and pre-filter our oil before pouring it into the engine. Especially for Toyota's.
My question is why don't we see some crazy number in VOA's with metal counts, silica and insolubles if this were a problem? (Not being sarcastic, actually asking...)
More BITOG gold....
Facts
* new oil can be very very dirty
* prefilling put the new oil on the engine side of the rock trap
* bypass is closed when the filter is passing air to pre-fill the engine
* the dirty oil that you are emptying into the engine gets to go through the filter first before the bearings
* even at that point IF the filter is in bypass, then some/most of the oil gets through the media.
* prefilling gives you more chance of dropping something bigger down the hole, which another poster has identified with bits of foil.
* there is no metal to metal contact on that start, as there's plenty of oil and tribofilm left from when the engine was running.
Another fact is that I have never seen an automotive maintenance document produced by an OEM that tells one to prefill a filter...would be very interested in seeing one, to make it my first.
Of COURSE manuals telling you not to prefill are not common (the big diesel example cited excepted), as telling you to not to do something that you wouldn't normally do is superfluous:
* don't add coolant to windshield washer fluid
* don't use icepick to clear windscreen.
Maybe we should all make remote filter mount pump setups with screw on 2 micron hydraulic filters and pre-filter our oil before pouring it into the engine. Especially for Toyota's.
My question is why don't we see some crazy number in VOA's with metal counts, silica and insolubles if this were a problem? (Not being sarcastic, actually asking...)
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Originally Posted by Shannow
...
* new oil can be very very dirty. ...
What's your evidence that any reputable brand of oil is likely to contain suspended "dirt" hard enough to cause damage?
Sayjac's point about adbvs seems reasonable, though. That's why I didn't worry excessively after noticing they tended to leak on long runs.
...
* new oil can be very very dirty. ...
What's your evidence that any reputable brand of oil is likely to contain suspended "dirt" hard enough to cause damage?
Sayjac's point about adbvs seems reasonable, though. That's why I didn't worry excessively after noticing they tended to leak on long runs.
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Originally Posted by CR94
Originally Posted by Shannow
...
* new oil can be very very dirty. ...
What's your evidence that any reputable brand of oil is likely to contain suspended "dirt" hard enough to cause damage?
Sayjac's point about adbvs seems reasonable, though. That's why I didn't worry excessively after noticing they tended to leak on long runs.
Note, that last part is YOUR words...I simply said that new oil can be very very dirty...
Cat recommends that new oil meet -/16/13, and get filtered from the container into the engine (we do it at work with hydraulic systems, as new oils … very very dirty...and yes, it plugs orifices in moog valve controllers unless filtered)
https://caterpillar.scene7.com/is/content/Caterpillar/C10467200
So, yes prefilling the filter, through the clean side of the filter, from the jug is poor practice.
Have I offered that "anything will blow up" ?
No...not likely.
Originally Posted by Shannow
...
* new oil can be very very dirty. ...
What's your evidence that any reputable brand of oil is likely to contain suspended "dirt" hard enough to cause damage?
Sayjac's point about adbvs seems reasonable, though. That's why I didn't worry excessively after noticing they tended to leak on long runs.
Note, that last part is YOUR words...I simply said that new oil can be very very dirty...
Cat recommends that new oil meet -/16/13, and get filtered from the container into the engine (we do it at work with hydraulic systems, as new oils … very very dirty...and yes, it plugs orifices in moog valve controllers unless filtered)
https://caterpillar.scene7.com/is/content/Caterpillar/C10467200
So, yes prefilling the filter, through the clean side of the filter, from the jug is poor practice.
Have I offered that "anything will blow up" ?
No...not likely.
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I had to make sure this was an actual thread. Just don't pour oil into the pan before starting. Problem solved.
Originally Posted by CR94
Originally Posted by Shannow
...
* new oil can be very very dirty. ...
What's your evidence that any reputable brand of oil is likely to contain suspended "dirt" hard enough to cause damage?
Sayjac's point about adbvs seems reasonable, though. That's why I didn't worry excessively after noticing they tended to leak on long runs.
Sure. I was under the impression that multi-pass efficiency is more meaningful, meaning stuff may get through.
Also, my uninstalled filter is hardly pristine. There are always loose fibers, metal shavings from the threads, and bits of cardboard that may have fallen from the box. A bit of unfiltered oil from a bottle is tiny.
I mean, what about the days when cans were common. Punching a hole can't be good if it introduces bits of metal.
Originally Posted by Shannow
...
* new oil can be very very dirty. ...
What's your evidence that any reputable brand of oil is likely to contain suspended "dirt" hard enough to cause damage?
Sayjac's point about adbvs seems reasonable, though. That's why I didn't worry excessively after noticing they tended to leak on long runs.
Sure. I was under the impression that multi-pass efficiency is more meaningful, meaning stuff may get through.
Also, my uninstalled filter is hardly pristine. There are always loose fibers, metal shavings from the threads, and bits of cardboard that may have fallen from the box. A bit of unfiltered oil from a bottle is tiny.
I mean, what about the days when cans were common. Punching a hole can't be good if it introduces bits of metal.
Originally Posted by Sayjac
Still difficult for me to accept that 100% of same new oil dumped down the fill hole never touches any bearings surface before going through the oil filter.
I think the worse that could happen is some of that oil going into the oil fill hole (if it's on a valve cover) is pour over a camshaft lobe, so it's possible a lobe/follower might get a split second of swipe on that oil film. Otherwise, pretty much all the oil poured into a valve cover just drains into the sump from the head drain hole(s).
Still difficult for me to accept that 100% of same new oil dumped down the fill hole never touches any bearings surface before going through the oil filter.
I think the worse that could happen is some of that oil going into the oil fill hole (if it's on a valve cover) is pour over a camshaft lobe, so it's possible a lobe/follower might get a split second of swipe on that oil film. Otherwise, pretty much all the oil poured into a valve cover just drains into the sump from the head drain hole(s).
Originally Posted by Shannow
* new oil can be very very dirty
It's possible it could be. I'll still pre-fill oil filters however, and as mentioned earlier I will not shake the jug or bottle before doing a filter pre-fill. My oil usually sits for a month or more before I use it (buy way in advance), so if anything can settle out it would have by the time I use the oil. If anything can stay in suspension for a month then it's most likely too small to even be captured in the oil filter.
* new oil can be very very dirty
It's possible it could be. I'll still pre-fill oil filters however, and as mentioned earlier I will not shake the jug or bottle before doing a filter pre-fill. My oil usually sits for a month or more before I use it (buy way in advance), so if anything can settle out it would have by the time I use the oil. If anything can stay in suspension for a month then it's most likely too small to even be captured in the oil filter.
Originally Posted by ZeeOSix
Originally Posted by Sayjac
Still difficult for me to accept that 100% of same new oil dumped down the fill hole never touches any bearings surface before going through the oil filter.
I think the worse that could happen is some of that oil going into the oil fill hole (if it's on a valve cover) is pour over a camshaft lobe, so it's possible a lobe/follower might get a split second of swipe on that oil film. Otherwise, pretty much all the oil poured into a valve cover just drains into the sump from the head drain hole(s).
I'm sure there are reports of long term cars where the oil fill hole is right over the cams/valves.
Originally Posted by Sayjac
Still difficult for me to accept that 100% of same new oil dumped down the fill hole never touches any bearings surface before going through the oil filter.
I think the worse that could happen is some of that oil going into the oil fill hole (if it's on a valve cover) is pour over a camshaft lobe, so it's possible a lobe/follower might get a split second of swipe on that oil film. Otherwise, pretty much all the oil poured into a valve cover just drains into the sump from the head drain hole(s).
I'm sure there are reports of long term cars where the oil fill hole is right over the cams/valves.
Originally Posted by y_p_w
Originally Posted by ZeeOSix
Originally Posted by Sayjac
Still difficult for me to accept that 100% of same new oil dumped down the fill hole never touches any bearings surface before going through the oil filter.
I think the worse that could happen is some of that oil going into the oil fill hole (if it's on a valve cover) is pour over a camshaft lobe, so it's possible a lobe/follower might get a split second of swipe on that oil film. Otherwise, pretty much all the oil poured into a valve cover just drains into the sump from the head drain hole(s).
I'm sure there are reports of long term cars where the oil fill hole is right over the cams/valves.
Of course ... and my point is that pouring oil out of the bottle onto the cam lob or two and it's followers won't hurt anything.
On a side note, my Tacoma V6 oil fill hole dumps the oil near the cam chain ... so if I pour it slowly it hits nothing and goes down to the sump.
Originally Posted by ZeeOSix
Originally Posted by Sayjac
Still difficult for me to accept that 100% of same new oil dumped down the fill hole never touches any bearings surface before going through the oil filter.
I think the worse that could happen is some of that oil going into the oil fill hole (if it's on a valve cover) is pour over a camshaft lobe, so it's possible a lobe/follower might get a split second of swipe on that oil film. Otherwise, pretty much all the oil poured into a valve cover just drains into the sump from the head drain hole(s).
I'm sure there are reports of long term cars where the oil fill hole is right over the cams/valves.
Of course ... and my point is that pouring oil out of the bottle onto the cam lob or two and it's followers won't hurt anything.
On a side note, my Tacoma V6 oil fill hole dumps the oil near the cam chain ... so if I pour it slowly it hits nothing and goes down to the sump.
Originally Posted by ZeeOSix
[... I'll still pre-fill oil filters however, and as mentioned earlier I will not shake the jug or bottle before doing a filter pre-fill. ...
That suggestion is so brilliant that I made it myself, a few posts back.
[... I'll still pre-fill oil filters however, and as mentioned earlier I will not shake the jug or bottle before doing a filter pre-fill. ...
That suggestion is so brilliant that I made it myself, a few posts back.
Originally Posted by CR94
Originally Posted by ZeeOSix
[... I'll still pre-fill oil filters however, and as mentioned earlier I will not shake the jug or bottle before doing a filter pre-fill. ...
That suggestion is so brilliant that I made it myself, a few posts back.
Yeah, just a small precaution that can't hurt if pre-filling filters.
Originally Posted by ZeeOSix
[... I'll still pre-fill oil filters however, and as mentioned earlier I will not shake the jug or bottle before doing a filter pre-fill. ...
That suggestion is so brilliant that I made it myself, a few posts back.
Yeah, just a small precaution that can't hurt if pre-filling filters.
i've always pre filled my filters if they were perfectly upright. And isn't prefilling a SOP on diesel engines anyway(not small things like VW TDIs, but light-duty ones like PSDs and the Cummins ISB/B5.9 and bigger ones)?
Originally Posted by DoubleWasp
Originally Posted by CT8
The bypass valve operates by the pressure differential between the unfiltered side of the filter element and the filtered side. If the oil filter is empty or the oil passages are empty the bypass valve will remain open until the oil pressure stabilizes with oil pressure on both sides of the element the bypass will "close"
Ummmm........what?
Until the oil travels far enough to encounter the resistance of the engine, how do you imagine the oil to be under much pressure at all? Empty cavities of air don't present a lot of resistance.
You are telling us the oil filter element doesn't cause a resistance to flow to the engine oil? What then would be the pressure differential between the oil on the dirty side of the filter element and the air on the clean side of the oil filter element .
Originally Posted by CT8
The bypass valve operates by the pressure differential between the unfiltered side of the filter element and the filtered side. If the oil filter is empty or the oil passages are empty the bypass valve will remain open until the oil pressure stabilizes with oil pressure on both sides of the element the bypass will "close"
Ummmm........what?
Until the oil travels far enough to encounter the resistance of the engine, how do you imagine the oil to be under much pressure at all? Empty cavities of air don't present a lot of resistance.
You are telling us the oil filter element doesn't cause a resistance to flow to the engine oil? What then would be the pressure differential between the oil on the dirty side of the filter element and the air on the clean side of the oil filter element .
Very, very little. But I dont want to get into the middle of that fight.
As far as prefilling a filter, if I were you guys I'd be a lot more concerned about the cleanliness of the filter before I'd worry about anything in the oil. I've done oil changes on maybe a dozen cars in the last year, and on every filter I have been able to wipe away metal flakes from the center threaded section, and a black, dusty dirty substance from the oil inlet holes and accessible interior exposed surfaces. Some of these metal flakes are alarming. Fram Ultras, Kia OEM, Mazda OEM, Purolators, you name it. Every single one of them. I wonder how many people actually think to do a thorough (as possible) cleaning of the filter surfaces before they install it. BITOG people, probably a high percentage. The rest of the world? Probably a very low percentage.
I fill the filter on my 240sx as much as I can, it sits almost sideways so its partially full at best, and I only do this because the timing chain makes a gawd-awful 3-4 second rattle if I dont. The rest of my cars...whatever. Sometimes I do, sometimes I dont. The Mazda filter for skyactiv's from the dealer has no drainback valve, so they are fairly easy to fill through the small inlet holes. Slow, but easy. Fill them up and no unfiltered oil goes through the engine.
In light of the evidence, I'm inclined to lean towards the "dont do it" camp. I've seen too many engines run with zero oil (or zero oil pressure) far longer than I ever thought they would, to think a few seconds of no pressure while the filter is filling after an oil change has any effect whatsoever.
My advise is, dont worry about the empty filter, worry about the dirty filter you're putting on.
As far as prefilling a filter, if I were you guys I'd be a lot more concerned about the cleanliness of the filter before I'd worry about anything in the oil. I've done oil changes on maybe a dozen cars in the last year, and on every filter I have been able to wipe away metal flakes from the center threaded section, and a black, dusty dirty substance from the oil inlet holes and accessible interior exposed surfaces. Some of these metal flakes are alarming. Fram Ultras, Kia OEM, Mazda OEM, Purolators, you name it. Every single one of them. I wonder how many people actually think to do a thorough (as possible) cleaning of the filter surfaces before they install it. BITOG people, probably a high percentage. The rest of the world? Probably a very low percentage.
I fill the filter on my 240sx as much as I can, it sits almost sideways so its partially full at best, and I only do this because the timing chain makes a gawd-awful 3-4 second rattle if I dont. The rest of my cars...whatever. Sometimes I do, sometimes I dont. The Mazda filter for skyactiv's from the dealer has no drainback valve, so they are fairly easy to fill through the small inlet holes. Slow, but easy. Fill them up and no unfiltered oil goes through the engine.
In light of the evidence, I'm inclined to lean towards the "dont do it" camp. I've seen too many engines run with zero oil (or zero oil pressure) far longer than I ever thought they would, to think a few seconds of no pressure while the filter is filling after an oil change has any effect whatsoever.
My advise is, dont worry about the empty filter, worry about the dirty filter you're putting on.
Originally Posted by CT8
Originally Posted by DoubleWasp
Originally Posted by CT8
The bypass valve operates by the pressure differential between the unfiltered side of the filter element and the filtered side. If the oil filter is empty or the oil passages are empty the bypass valve will remain open until the oil pressure stabilizes with oil pressure on both sides of the element the bypass will "close"
Ummmm........what?
Until the oil travels far enough to encounter the resistance of the engine, how do you imagine the oil to be under much pressure at all? Empty cavities of air don't present a lot of resistance.
You are telling us the oil filter element doesn't cause a resistance to flow to the engine oil? What then would be the pressure differential between the oil on the dirty side of the filter element and the air on the clean side of the oil filter element .
Like I said before ... the delta-p across the media is dependent on the oil viscosity and oil flow. That would be no different if the filter is full of air or full of oil.
Originally Posted by DoubleWasp
Originally Posted by CT8
The bypass valve operates by the pressure differential between the unfiltered side of the filter element and the filtered side. If the oil filter is empty or the oil passages are empty the bypass valve will remain open until the oil pressure stabilizes with oil pressure on both sides of the element the bypass will "close"
Ummmm........what?
Until the oil travels far enough to encounter the resistance of the engine, how do you imagine the oil to be under much pressure at all? Empty cavities of air don't present a lot of resistance.
You are telling us the oil filter element doesn't cause a resistance to flow to the engine oil? What then would be the pressure differential between the oil on the dirty side of the filter element and the air on the clean side of the oil filter element .
Like I said before ... the delta-p across the media is dependent on the oil viscosity and oil flow. That would be no different if the filter is full of air or full of oil.
Originally Posted by ZeeOSix
Originally Posted by CT8
Originally Posted by DoubleWasp
Originally Posted by CT8
The bypass valve operates by the pressure differential between the unfiltered side of the filter element and the filtered side. If the oil filter is empty or the oil passages are empty the bypass valve will remain open until the oil pressure stabilizes with oil pressure on both sides of the element the bypass will "close"
Ummmm........what?
Until the oil travels far enough to encounter the resistance of the engine, how do you imagine the oil to be under much pressure at all? Empty cavities of air don't present a lot of resistance.
You are telling us the oil filter element doesn't cause a resistance to flow to the engine oil? What then would be the pressure differential between the oil on the dirty side of the filter element and the air on the clean side of the oil filter element .
Like I said before ... the delta-p across the media is dependent on the oil viscosity and oil flow. That would be no different if the filter is full of air or full of oil.
It does
Originally Posted by CT8
Originally Posted by DoubleWasp
Originally Posted by CT8
The bypass valve operates by the pressure differential between the unfiltered side of the filter element and the filtered side. If the oil filter is empty or the oil passages are empty the bypass valve will remain open until the oil pressure stabilizes with oil pressure on both sides of the element the bypass will "close"
Ummmm........what?
Until the oil travels far enough to encounter the resistance of the engine, how do you imagine the oil to be under much pressure at all? Empty cavities of air don't present a lot of resistance.
You are telling us the oil filter element doesn't cause a resistance to flow to the engine oil? What then would be the pressure differential between the oil on the dirty side of the filter element and the air on the clean side of the oil filter element .
Like I said before ... the delta-p across the media is dependent on the oil viscosity and oil flow. That would be no different if the filter is full of air or full of oil.
It does
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