On both my vehicles I always pre soak the filter media in clean oil before installing it. Neither has a vertical mounted filter that I could fill; one is a top mount Subaru and the other a side mount Toyota catridge style filter. I picked up this habit from a relative who was an engineer and mentioned that a filter only filters when it's soaked in the media it needs to filter. Anyone else do this?
Anyone else pre-soak the filter?
- Thread starter jqgz
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JHZR2
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I usually pre fill spin on filters. Never gave much thought to vertical cartridge filters...
I do if it doesn't make too much of a mess.
Even half way is good cuz the media soakes up the oil.
The 3 TSXs I service are horrible... The other cars are fine.
Even half way is good cuz the media soakes up the oil.
The 3 TSXs I service are horrible... The other cars are fine.
Never done it with a cartridge filter, Guess I could on my Santa Fe, but really pointless IMO.
Being top mounted, there is not way to keep the filter slot filled, so it would still be empty on startup. What good would having already oiled media do for that 2 seconds while it fills?
For canister filters that mount thread end up I fill almost full. For sideways mounted, I fill 1/2 way and let it soak in, then add a little more right before I fill.
But only sometimes do I do this.
Being top mounted, there is not way to keep the filter slot filled, so it would still be empty on startup. What good would having already oiled media do for that 2 seconds while it fills?
For canister filters that mount thread end up I fill almost full. For sideways mounted, I fill 1/2 way and let it soak in, then add a little more right before I fill.
But only sometimes do I do this.
A top mount filter you can still pre-fill. You pour in enough that it soaks it up. Any oil left in the center tube, you can drain out back into the fresh oil container or crankcase. Use the mess you made on the filter to lube the O-ring.
Vertical cartridge filters, again, yes you can. You can only fill up as much as the media and whatever housing type it is takes.
Vertical cartridge filters, again, yes you can. You can only fill up as much as the media and whatever housing type it is takes.
Ob2 gm cars have a mode called clear flood mode. If you step on the gas to the floor and turn the starter it won't start. I'll spin the engine over until the oil light goes out. Everything else get a lil oil in it if it wont make a mess. Some cars like ford small blocks and 4.6l filters have a tilt so I dont feel them all the way.
Originally Posted by jqgz
I picked up this habit from a relative who was an engineer and mentioned that a filter only filters when it's soaked in the media it needs to filter. Anyone else do this?
Why would a filter only filter if the media was pre-soaked with oil, lol. Some guys have some strange conceptions.
And yes, I pre-soak the media just because doing so also adds a bit more oil in the filter than just what the media can absorb.
I picked up this habit from a relative who was an engineer and mentioned that a filter only filters when it's soaked in the media it needs to filter. Anyone else do this?
Why would a filter only filter if the media was pre-soaked with oil, lol. Some guys have some strange conceptions.
And yes, I pre-soak the media just because doing so also adds a bit more oil in the filter than just what the media can absorb.
Originally Posted by jqgz
I picked up this habit from a relative who was an engineer and mentioned that a filter only filters when it's soaked in the media it needs to filter. Anyone else do this?
Maybe he's getting confused with K&N air filters. They filter better when they are dirty. OCD of clean oiled K&N air filters does more harm than good.
I picked up this habit from a relative who was an engineer and mentioned that a filter only filters when it's soaked in the media it needs to filter. Anyone else do this?
Maybe he's getting confused with K&N air filters. They filter better when they are dirty. OCD of clean oiled K&N air filters does more harm than good.
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Maybe your relative/engineer means that...a completely dry(just installed new filter) will go into bypass mode unless it has oil in it. So that the engine gets enough lubrication upon startup right after a fresh OCI...???
I mean, was there more to your relative's statement; a caveat to or a reason for their comment?
Or did your relative just make the statement and leave it go at that?
Were there any follow up questions asked to the relative/engineer? You know like, can you(engineer) elaborate further?
I mean, was there more to your relative's statement; a caveat to or a reason for their comment?
Or did your relative just make the statement and leave it go at that?
Were there any follow up questions asked to the relative/engineer? You know like, can you(engineer) elaborate further?
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I used to do it all the time on everything I could until I got ocd about the non filtered oil going in the clean side of the filter. This discussion has come up on here before. I still don't know whether it's better to have quicker oil pressure, or only oil that's already been filtered going straight to the bearings.
Cartridge filters I always did it in on customers ecotec engines in Cobalt's and cavalier's etc because the timing chain would rattle badly on first start after an oil change until I started soaking the cartridge before hand.
My personal cars don't make any dry noises even if I don't pre fill so I don't anymore. The 05 truck I could do the clear flood mode thing mentioned above, never thought about it before.
Cartridge filters I always did it in on customers ecotec engines in Cobalt's and cavalier's etc because the timing chain would rattle badly on first start after an oil change until I started soaking the cartridge before hand.
My personal cars don't make any dry noises even if I don't pre fill so I don't anymore. The 05 truck I could do the clear flood mode thing mentioned above, never thought about it before.
Always....shaves several seconds off the low oil pressure time on startup.
If you do this you are supposed to fill it through the small holes. If you pour it into the big hole and there is any contamination in the oil or bottle it will go straight into the bearings unfiltered.
Originally Posted by Chris142
If you do this you are supposed to fill it through the small holes. If you pour it into the big hole and there is any contamination in the oil or bottle it will go straight into the bearings unfiltered.
This is why it's important to check for metal shavings on the threads.
Dont believe filling it will change anything, I believe oil is pretty free of contanimants.
How in the world would you fill thru the small holes?
If you do this you are supposed to fill it through the small holes. If you pour it into the big hole and there is any contamination in the oil or bottle it will go straight into the bearings unfiltered.
This is why it's important to check for metal shavings on the threads.
Dont believe filling it will change anything, I believe oil is pretty free of contanimants.
How in the world would you fill thru the small holes?
I do not.
I once went to install a filter from a store that I won't name, but it rhymes with Vautozone. The threads were apparently messed up on the filter (it was the same one as the filter I removed from the vehicle). I pre-filled the filter a bit, went to install it, and no dice, it wouldn't even begin to thread on. Cleaned it out the best I could, but they still wouldn't take it back because it had been "used". While I'm sure other stores might differ in their policy, I haven't pre-filled a filter since, and don't see a benefit unless starting a brand new or rebuilt engine that has never had oil in it.
I once went to install a filter from a store that I won't name, but it rhymes with Vautozone. The threads were apparently messed up on the filter (it was the same one as the filter I removed from the vehicle). I pre-filled the filter a bit, went to install it, and no dice, it wouldn't even begin to thread on. Cleaned it out the best I could, but they still wouldn't take it back because it had been "used". While I'm sure other stores might differ in their policy, I haven't pre-filled a filter since, and don't see a benefit unless starting a brand new or rebuilt engine that has never had oil in it.
Originally Posted by tblt44
Originally Posted by Chris142
If you do this you are supposed to fill it through the small holes. If you pour it into the big hole and there is any contamination in the oil or bottle it will go straight into the bearings unfiltered.
This is why it's important to check for metal shavings on the threads.
Dont believe filling it will change anything, I believe oil is pretty free of contanimants.
How in the world would you fill thru the small holes?
I've tried. It's very time consuming the way I tried to do it. I've read somewhere that there is no cleanliness standard for fresh motor oil. I don't know whether that is true or not. I would think most oil should be pretty clean straight out of the bottle, but if it were not it would be after going through the filter. Which is why people suggest not doing this or filling through the dirty side holes.
Originally Posted by Chris142
If you do this you are supposed to fill it through the small holes. If you pour it into the big hole and there is any contamination in the oil or bottle it will go straight into the bearings unfiltered.
This is why it's important to check for metal shavings on the threads.
Dont believe filling it will change anything, I believe oil is pretty free of contanimants.
How in the world would you fill thru the small holes?
I've tried. It's very time consuming the way I tried to do it. I've read somewhere that there is no cleanliness standard for fresh motor oil. I don't know whether that is true or not. I would think most oil should be pretty clean straight out of the bottle, but if it were not it would be after going through the filter. Which is why people suggest not doing this or filling through the dirty side holes.
I haven't pre-filled a filter since, and don't see a benefit unless starting a brand new or rebuilt engine that has never had oil in it.
I'm the same. Only on reman, rebuilds, and new/crate engines have I ever filled the filters before starting. Even then engines I've done (SB & BB Chev) I would pre-lubed with drill and pre-lube tool for several minutes before cranking. After any engine has been run the 1.5 seconds without oil pressure doesn't hurt anything. If you've ever disassembled an engine you would be comfortable starting it without filling the oil filter. Everything stays coated and slippery with oil.
I'm the same. Only on reman, rebuilds, and new/crate engines have I ever filled the filters before starting. Even then engines I've done (SB & BB Chev) I would pre-lubed with drill and pre-lube tool for several minutes before cranking. After any engine has been run the 1.5 seconds without oil pressure doesn't hurt anything. If you've ever disassembled an engine you would be comfortable starting it without filling the oil filter. Everything stays coated and slippery with oil.
Does it really help? On a large filter, probably somewhat. Dunno for sure.
It makes me sleep better.
It makes me sleep better.
