I think there is a link here where some "car guru" said this, which is nonsense. I have cartridge filters on my cars, but I do pre-fill may parents filters. Actually, I just coat the metal face and soak the pleats...
Never Prefill oil filters!
- Thread starter Vern_in_IL
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As much as we are crucifying the OP, there "can" be some legitimate concerns about his claims. Back in the day when we actually had some meaningful discussions about oil, we did bring up concerns about overly dirty NEW oil.
Here is just one discussion with data: https://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2590703
From expert Jim Allen: " I don't have permission, yet, from my source to post all the info, but I can say the cleanest bottled oil on the list is DELO 400 15W40 at 19/18/17 and the dirtiest is Mopar MaxPro 15W40 at 23/21/16. The list is heavy on HDEOs. I have some bulk oil tests that would make you hurl and vow never to buy bulk oil again. This appears to be a known problem in the lube industry but one that many in the retail side tend to ignore."
I don't worry about this issue in my applications.
Here is just one discussion with data: https://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2590703
From expert Jim Allen: " I don't have permission, yet, from my source to post all the info, but I can say the cleanest bottled oil on the list is DELO 400 15W40 at 19/18/17 and the dirtiest is Mopar MaxPro 15W40 at 23/21/16. The list is heavy on HDEOs. I have some bulk oil tests that would make you hurl and vow never to buy bulk oil again. This appears to be a known problem in the lube industry but one that many in the retail side tend to ignore."
I don't worry about this issue in my applications.
Originally Posted by gathermewool
Sure you can. The filter media will hold around half of its volume and you won't lose one drop. I'd rather install a filter with wetted media (even if no where near full to the brim, as could be done on the old EJ engines) than a bone-dry filter.
You must live in some anti-gravity environment. I pre-fill filters with a few ounces of oil and let it sit to absorb into the media. On my horizontally-mounted filter locations, oil still spills out.
Sure you can. The filter media will hold around half of its volume and you won't lose one drop. I'd rather install a filter with wetted media (even if no where near full to the brim, as could be done on the old EJ engines) than a bone-dry filter.
You must live in some anti-gravity environment. I pre-fill filters with a few ounces of oil and let it sit to absorb into the media. On my horizontally-mounted filter locations, oil still spills out.
Sorry dudes but I disagree with everything you say.... you may not realise it but dirty oil can come right out of your bottle or barrel, we have had oil samples tested to verify that and in some cases the oil was dirtier out fresh barrel(bulk) than the oil drained out of the pan at 20000 miles. The fuel and oil you buy is NOT clean enough to meet their specifications until it is filtered. If you pour "new" oil or fuel into the clean side of a filter, you have just contaminated that filter.
These manufacturers spend hundreds of millions of dollars on R&D. I don't care if your dad and grand-dad taught you to fill your filters, it is an incorrect procedure.
Take the used oil filter at a normal change interval straight from the engine and carefully extract an oil sample from the center with a turkey baster. This is the filtered oil that was continuously running for numerous hours in the engine up to the point when the filter was removed. Have that sample analyzed. Now pour clean oil straight from the container into a sample jar, this is the oil that will run thru the engine for a few seconds if you pour it into the center of the filter.
Have that sample analyzed as well. Then show how the unfiltered new oil for a few seconds caused the bearing damage and the high-hours filtered oil could not have possibly caused any bearing damage or clogged a piston cooling jet, even with the possibility of momentary bypass such as in extreme cold start-up. The bottom line is due care must be taken to keep contamination or debris away from the inlet of the new oil filter during handling.
These manufacturers spend hundreds of millions of dollars on R&D. I don't care if your dad and grand-dad taught you to fill your filters, it is an incorrect procedure.
Take the used oil filter at a normal change interval straight from the engine and carefully extract an oil sample from the center with a turkey baster. This is the filtered oil that was continuously running for numerous hours in the engine up to the point when the filter was removed. Have that sample analyzed. Now pour clean oil straight from the container into a sample jar, this is the oil that will run thru the engine for a few seconds if you pour it into the center of the filter.
Have that sample analyzed as well. Then show how the unfiltered new oil for a few seconds caused the bearing damage and the high-hours filtered oil could not have possibly caused any bearing damage or clogged a piston cooling jet, even with the possibility of momentary bypass such as in extreme cold start-up. The bottom line is due care must be taken to keep contamination or debris away from the inlet of the new oil filter during handling.
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Where practicable I pre-fill the filter and will continue to do so. Sure it's mostly a feel good preference thing, but that's ok. I'm not sure what the "significant" difference is between dumping several ounces of new oil in a filter versus the rest of an entire jug down the fill hole? Both are new unfiltered oil.
And some members have claimed that to be absolutely safe about the oil, one should change the oil, leave the old filter on, then some time after the OC change filter. Supposedly some science behind it too.
I won't be doing that.
And this topic has been covered often on bitog. Linked is one I remember commenting in not too long ago.
https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/4810645/1
And some members have claimed that to be absolutely safe about the oil, one should change the oil, leave the old filter on, then some time after the OC change filter. Supposedly some science behind it too.
And this topic has been covered often on bitog. Linked is one I remember commenting in not too long ago.
https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/4810645/1
I'm not aware of any passenger car or light duty truck applications which call for a pre-fill by the manufacturer. So it isn't necessary, but I don't see the harm in it. I do pre-fill my truck oil filter since it is larger than either of the two cars and it is in a location which allow for pre-filling. I'm not worried about unfiltered oil since that will happen any time it is in bypass, and I find it hard to believe that modern quality oils would have any substantial particles which would cause harm.
Now City Star or one of those other junk oils found in some convenience stores would be a different story.
Now City Star or one of those other junk oils found in some convenience stores would be a different story.
Originally Posted by Vern_in_IL
Sorry dudes but I disagree with everything you say.... you may not realise it but dirty oil can come right out of your bottle or barrel,
It must have been 10 years ago or more, but I remember Caterpillar put some reminders in some of their new oil filter boxes that said not to prefill their oil filters. I'm pretty sure they even issued a TSB about it. That being said, there are a lot of diesel mechanics out there that work in the dirtiest conditions and seem not to care about cleanliness and I'm sure it was because old oil was being used to prefill new oil filters.
I have no problem prefilling an oil filter that sits vertical, but a lot of my Ford applications have the filters sitting at a 45° and I'd rather not prefill them. I also have a '98 Ranger with the 3.0 V6 that is a royal PITA to change an oil filter. There's is no way I'd try to add oil to it, especially since I have oil pressure in less than a second after changing oil anyway.
Sorry dudes but I disagree with everything you say.... you may not realise it but dirty oil can come right out of your bottle or barrel,
It must have been 10 years ago or more, but I remember Caterpillar put some reminders in some of their new oil filter boxes that said not to prefill their oil filters. I'm pretty sure they even issued a TSB about it. That being said, there are a lot of diesel mechanics out there that work in the dirtiest conditions and seem not to care about cleanliness and I'm sure it was because old oil was being used to prefill new oil filters.
I have no problem prefilling an oil filter that sits vertical, but a lot of my Ford applications have the filters sitting at a 45° and I'd rather not prefill them. I also have a '98 Ranger with the 3.0 V6 that is a royal PITA to change an oil filter. There's is no way I'd try to add oil to it, especially since I have oil pressure in less than a second after changing oil anyway.
Kestas
Staff member
My colleague once filtered 12 quarts of transmission fluid before putting it in his transmission. He showed me the debris that came out. There was some, but not enough to get me excited.
If people are truly concerned, could you prefill by filling in the dirty side of the filter?
If people are truly concerned, could you prefill by filling in the dirty side of the filter?
3.5 Ecoboost has a horizontal filter, no can prefill. About 4 seconds till oil pressure rise. Damage done: minimal to none.
This is why I prime my vehicles before starting them after an oil change. Simply put the gas pedal to the floor. This shuts off fuel in Ford's since the 1990's or so. Crank till the oil pressure gauge is in the normal range. Then I'll start it.
I prefill sometimes but the Op has a point. Had a fram ultra that I got some oil in the inlet holes only to see fine metal flakes come from under the baseplate. I posted about it on here and nobody seemed to have much to say.
May want to keep an eye out for manufacturing leftovers.
May want to keep an eye out for manufacturing leftovers.
If one is that worried about grit and dirt in their brand new motor oil, then they should be equally concerned about the same debris being left on their exterior filter media and filter exit plenum during the manufacturing process. Consistency and logic demands this.
If you aren't entirely flushing or air blowing clean your BRAND NEW filter before installation, then you are leaving yourself open to the exact same risk of debris introduction into your engine as not "filtering" the new oil. I've yet to hear of anyone flushing or soaking their new filters with pre-filtered oil and/or pressurized clean/filtered air in order to remove ALL potential contaminants. Think of all the fine metal shavings that could still be in the filter exit plenum or adhered to the filter media after assembly? There's no way it's 100% clean. And think about all the dirty places that filter sat in the cheaply made box where it could have picked all sorts of debris before you install it. They don't even come from the mfg with a "clean seal" on the filter opening. More to think about....for this with plenty of time me to think....
If pre-filling oil filters was such an onerous and risky practice, wouldn't there be a warning about such buffoonery in the owner's manual?
If you aren't entirely flushing or air blowing clean your BRAND NEW filter before installation, then you are leaving yourself open to the exact same risk of debris introduction into your engine as not "filtering" the new oil. I've yet to hear of anyone flushing or soaking their new filters with pre-filtered oil and/or pressurized clean/filtered air in order to remove ALL potential contaminants. Think of all the fine metal shavings that could still be in the filter exit plenum or adhered to the filter media after assembly? There's no way it's 100% clean. And think about all the dirty places that filter sat in the cheaply made box where it could have picked all sorts of debris before you install it. They don't even come from the mfg with a "clean seal" on the filter opening. More to think about....for this with plenty of time me to think....
If pre-filling oil filters was such an onerous and risky practice, wouldn't there be a warning about such buffoonery in the owner's manual?
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There is "some" truth to this mentality... but it almost certainly won't affect an internal combustion engine in a disastrous way. Now, if we were talking about some of Shannow's turbines, and you dumped in 500 gallons of oil straight out of a jug without using a pre-filter cart, then you may actually be doing significant damage.
If you hop over to the VOA section, I had 4 VOAs done with particle counts. Ravenol was the cleanest, PUP was 2nd, Motul 4100 Power I believe third, and Delo XLE was the the worst. Even though the ISO numbers were only 4-5 different, this is a count of THOUSANDS of additional particles of a given size, and the Delo actually had some particles >50 microns! Now... prefilling most filters will take somewhere between a pint and a quart to fill, and put these particles on the "clean" side of your filter. If your oil tested very clean on the PC, you have almost nothing to worry about because 99.99% of everything smaller than ~15-20 microns is going through the filter anyways.
Me, I am a stubborn bird. All my engines are PFI, all my engines are non-Dexos nor require "special" oils, and I prefill my filters because I choose to try to prevent 1-2 seconds of metal-on-metal contact as the pump builds pressure throughout the engine after an OCI. However, you can do whatever you choose. Filling or not prefilling the filter on a car is not going to be the thing that keeps it from not making it 300k miles.
If you hop over to the VOA section, I had 4 VOAs done with particle counts. Ravenol was the cleanest, PUP was 2nd, Motul 4100 Power I believe third, and Delo XLE was the the worst. Even though the ISO numbers were only 4-5 different, this is a count of THOUSANDS of additional particles of a given size, and the Delo actually had some particles >50 microns! Now... prefilling most filters will take somewhere between a pint and a quart to fill, and put these particles on the "clean" side of your filter. If your oil tested very clean on the PC, you have almost nothing to worry about because 99.99% of everything smaller than ~15-20 microns is going through the filter anyways.
Me, I am a stubborn bird. All my engines are PFI, all my engines are non-Dexos nor require "special" oils, and I prefill my filters because I choose to try to prevent 1-2 seconds of metal-on-metal contact as the pump builds pressure throughout the engine after an OCI. However, you can do whatever you choose. Filling or not prefilling the filter on a car is not going to be the thing that keeps it from not making it 300k miles.
Originally Posted by Vern_in_IL
Sorry dudes but I disagree with everything you say.... you may not realise it but dirty oil can come right out of your bottle or barrel, we have had oil samples tested to verify that and in some cases the oil was dirtier out fresh barrel(bulk) than the oil drained out of the pan at 20000 miles. The fuel and oil you buy is NOT clean enough to meet their specifications until it is filtered. If you pour "new" oil or fuel into the clean side of a filter, you have just contaminated that filter.
These manufacturers spend hundreds of millions of dollars on R&D. I don't care if your dad and grand-dad taught you to fill your filters, it is an incorrect procedure.
Take the used oil filter at a normal change interval straight from the engine and carefully extract an oil sample from the center with a turkey baster. This is the filtered oil that was continuously running for numerous hours in the engine up to the point when the filter was removed. Have that sample analyzed. Now pour clean oil straight from the container into a sample jar, this is the oil that will run thru the engine for a few seconds if you pour it into the center of the filter.
Have that sample analyzed as well. Then show how the unfiltered new oil for a few seconds caused the bearing damage and the high-hours filtered oil could not have possibly caused any bearing damage or clogged a piston cooling jet, even with the possibility of momentary bypass such as in extreme cold start-up. The bottom line is due care must be taken to keep contamination or debris away from the inlet of the new oil filter during handling.
That is up to you to do. Provide a video so details of cleanliness can be viewed. You probably take your unsealed oil filters out of an unsealed cardboard box that has been sitting around some time, don't you. They also sat somewhere else a long time before you got them and were handled and made in a factory with all the parts exposed to factory dust and dirt. If from walmart someone may have taken it home and returned it in a dust storm, who knows what happens All those loose particles from manufacturing handling and storage of unknown composition are waiting. Buy those Asian covered filters.
Sorry dudes but I disagree with everything you say.... you may not realise it but dirty oil can come right out of your bottle or barrel, we have had oil samples tested to verify that and in some cases the oil was dirtier out fresh barrel(bulk) than the oil drained out of the pan at 20000 miles. The fuel and oil you buy is NOT clean enough to meet their specifications until it is filtered. If you pour "new" oil or fuel into the clean side of a filter, you have just contaminated that filter.
These manufacturers spend hundreds of millions of dollars on R&D. I don't care if your dad and grand-dad taught you to fill your filters, it is an incorrect procedure.
Take the used oil filter at a normal change interval straight from the engine and carefully extract an oil sample from the center with a turkey baster. This is the filtered oil that was continuously running for numerous hours in the engine up to the point when the filter was removed. Have that sample analyzed. Now pour clean oil straight from the container into a sample jar, this is the oil that will run thru the engine for a few seconds if you pour it into the center of the filter.
Have that sample analyzed as well. Then show how the unfiltered new oil for a few seconds caused the bearing damage and the high-hours filtered oil could not have possibly caused any bearing damage or clogged a piston cooling jet, even with the possibility of momentary bypass such as in extreme cold start-up. The bottom line is due care must be taken to keep contamination or debris away from the inlet of the new oil filter during handling.
That is up to you to do. Provide a video so details of cleanliness can be viewed. You probably take your unsealed oil filters out of an unsealed cardboard box that has been sitting around some time, don't you. They also sat somewhere else a long time before you got them and were handled and made in a factory with all the parts exposed to factory dust and dirt. If from walmart someone may have taken it home and returned it in a dust storm, who knows what happens All those loose particles from manufacturing handling and storage of unknown composition are waiting. Buy those Asian covered filters.
Originally Posted by advocate
This is why I prime my vehicles before starting them after an oil change. Simply put the gas pedal to the floor. This shuts off fuel in Ford's since the 1990's or so. Crank till the oil pressure gauge is in the normal range. Then I'll start it.
This does not apply to all makes. I know you didn't claim that it does, I just want to clarify for others.
This is why I prime my vehicles before starting them after an oil change. Simply put the gas pedal to the floor. This shuts off fuel in Ford's since the 1990's or so. Crank till the oil pressure gauge is in the normal range. Then I'll start it.
This does not apply to all makes. I know you didn't claim that it does, I just want to clarify for others.
I have read (not experienced, thank God) that if any bits of foil make it into the center of the oil filter when prefilling that it is possible to plug an engine oil squirter (Cummins 5.9/ISB anecdote). Which is the same issue that the older disintegrating Fram filters caused way back in the late '90s/early '00s (solved with the introduction of the PH3976A, the PH3976 was the dangerous one). If the filter is prefilled from the outside & NO unfiltered oil is put in the center, then it would be OK. I just crank without glowing first on the diesels or with the gas pedal floored on the (EFI) gassers until oil pressure starts coming up.
BMW motorcycles recommends prefilling oil filters. There have been cam chain guides breaking from no oil pressure.
In Kohler courage engines prefilling is essential as it takes way to long for the little oil pump to fill it and there is NO splash lube. This is why they throw rods.
Of course there are lots of other problems but this is one. There are probably other examples.
Blanket statements are often wrong. I would say always but that would be a blanket statement
Rod
In Kohler courage engines prefilling is essential as it takes way to long for the little oil pump to fill it and there is NO splash lube. This is why they throw rods.
Of course there are lots of other problems but this is one. There are probably other examples.
Blanket statements are often wrong. I would say always but that would be a blanket statement
Rod
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gathermewool
Site Donor 2023
Originally Posted by hallstevenson
Originally Posted by gathermewool
Sure you can. The filter media will hold around half of its volume and you won't lose one drop. I'd rather install a filter with wetted media (even if no where near full to the brim, as could be done on the old EJ engines) than a bone-dry filter.
You must live in some anti-gravity environment. I pre-fill filters with a few ounces of oil and let it sit to absorb into the media. On my horizontally-mounted filter locations, oil still spills out.
I have the same engine as you in my '14 FXT. The FB25 in my Legacy is oriented the same exact way.
I don't know what to tell you, but you can get a good amount of oil into the filter, way more than a few oz.
Do you also have issues with oil spilling everywhere when you remove the filter, too? I have MINIMAL cleanup within the filter containment cup using Fram Ultra filters.
Originally Posted by gathermewool
Sure you can. The filter media will hold around half of its volume and you won't lose one drop. I'd rather install a filter with wetted media (even if no where near full to the brim, as could be done on the old EJ engines) than a bone-dry filter.
You must live in some anti-gravity environment. I pre-fill filters with a few ounces of oil and let it sit to absorb into the media. On my horizontally-mounted filter locations, oil still spills out.
I have the same engine as you in my '14 FXT. The FB25 in my Legacy is oriented the same exact way.
I don't know what to tell you, but you can get a good amount of oil into the filter, way more than a few oz.
Do you also have issues with oil spilling everywhere when you remove the filter, too? I have MINIMAL cleanup within the filter containment cup using Fram Ultra filters.
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