I have always pre-filled the filters before I put them on, never had a problem. At work, they always pre-fill the filters for the truck engines before putting them on. Those are big filters and hold quiet a bit of oil. I wouldn't want to start one with an empty filter and wait for it to pump it full before getting oil flowing to the main and rod bearings.
Never Prefill oil filters!
- Thread starter Vern_in_IL
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With all of the VOAs we have on this site & others, I don't think that virgin oil is dirty enough to concern ourselves with at all.
What about all of the new virgin oil we're pouring in over the top of our engines to replace all of the oil we drained out?
What about all of the new virgin oil we're pouring in over the top of our engines to replace all of the oil we drained out?
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Originally Posted by Vern_in_IL
Because the oil you add will go right into the engine unfiltered!
An acquaintance rinses every new oil filter with at least a quart of fresh oil before installing the filter. He is convinced that a factory-fresh oil filter contains residual particles like metal shavings that will destroy his engine if he doesn't flush them out. I did not see the shavings he showed me. As I just mentioned in another post, rationalizing behavor may prevent some people from just snapping. I do prefill oil filters, especially large ones, but not so that there will be a mess when putting the filter on.
Because the oil you add will go right into the engine unfiltered!
An acquaintance rinses every new oil filter with at least a quart of fresh oil before installing the filter. He is convinced that a factory-fresh oil filter contains residual particles like metal shavings that will destroy his engine if he doesn't flush them out. I did not see the shavings he showed me. As I just mentioned in another post, rationalizing behavor may prevent some people from just snapping. I do prefill oil filters, especially large ones, but not so that there will be a mess when putting the filter on.
Originally Posted by ragtoplvr
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.
Wow... didn't know that. Thanks for the info! I ended up putting a Fram Ultra (I think it was the XG3614) on my mom's 17HP Courage lawn mower... because everything with the original filter matched up perfectly to the 3614, and I had an extra one on hand I wasn't going to use! All her OPE is currently running Mobil1 TDT 5W40 since it was on sale LOL
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.
Wow... didn't know that. Thanks for the info! I ended up putting a Fram Ultra (I think it was the XG3614) on my mom's 17HP Courage lawn mower... because everything with the original filter matched up perfectly to the 3614, and I had an extra one on hand I wasn't going to use! All her OPE is currently running Mobil1 TDT 5W40 since it was on sale LOL
Originally Posted by vavavroom
An acquaintance rinses every new oil filter with at least a quart of fresh oil before installing the filter.
How exactly does he do that? You can't exactly get new oil in past the ADBV, and if you pour it in the center tube it's not all going to come back out as it will soak into the filter media. Please explain!
An acquaintance rinses every new oil filter with at least a quart of fresh oil before installing the filter.
How exactly does he do that? You can't exactly get new oil in past the ADBV, and if you pour it in the center tube it's not all going to come back out as it will soak into the filter media. Please explain!
Originally Posted by Char Baby
With all of the VOAs we have on this site & others, I don't think that virgin oil is dirty enough to concern ourselves with at all.
Only a VOA with particle counts will really tell you how "dirty" an oil is. Take a look at the VOAs I got from TestOil on a couple oils last month- there are literally THOUSANDS more particles in the Delo XLE and Motul 4100 Power than there are in the Ravenol DXG or Pennzoil Ultra Platinum.
With all of the VOAs we have on this site & others, I don't think that virgin oil is dirty enough to concern ourselves with at all.
Only a VOA with particle counts will really tell you how "dirty" an oil is. Take a look at the VOAs I got from TestOil on a couple oils last month- there are literally THOUSANDS more particles in the Delo XLE and Motul 4100 Power than there are in the Ravenol DXG or Pennzoil Ultra Platinum.
A guy posts something stupid and we get 5 pages in his thread. Love da internet!
Originally Posted by SubieRubyRoo
Originally Posted by vavavroom
An acquaintance rinses every new oil filter with at least a quart of fresh oil before installing the filter.
How exactly does he do that? You can't exactly get new oil in past the ADBV, and if you pour it in the center tube it's not all going to come back out as it will soak into the filter media. Please explain!
I would have to speculate since I have never watched him wasting a quart of fresh oil with this nutty procedure. It's not a rational act, just rationalizing behavior that makes him feel good. He's the same guy who will park his vehicle no closer than one block from the ocean because he is convinced his car will spontaneously rust out if he parks any closer. Nevermind that salty air moves inland at least 10 blocks.
Originally Posted by vavavroom
An acquaintance rinses every new oil filter with at least a quart of fresh oil before installing the filter.
How exactly does he do that? You can't exactly get new oil in past the ADBV, and if you pour it in the center tube it's not all going to come back out as it will soak into the filter media. Please explain!
I would have to speculate since I have never watched him wasting a quart of fresh oil with this nutty procedure. It's not a rational act, just rationalizing behavior that makes him feel good. He's the same guy who will park his vehicle no closer than one block from the ocean because he is convinced his car will spontaneously rust out if he parks any closer. Nevermind that salty air moves inland at least 10 blocks.
Originally Posted by SubieRubyRoo
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.
Maybe with a filter rated at 50% at 100 microns.
Most high efficiency oil filters are going to filter around 70~80% at 5~10 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.
Maybe with a filter rated at 50% at 100 microns.
Most high efficiency oil filters are going to filter around 70~80% at 5~10 microns.
From Advance Auto Parts " Fill the new filter with about ½ quart of oil so it will be pre-loaded when the engine starts."
https://shop.advanceautoparts.com/r/advice/car-maintenance/how-to-change-oil-filter
From Autozone "Partially filling the new filter with oil will reduce the time the engine must run dry when starting."
https://www.autozone.com/repairinfo/repairguide/repairGuideContent.jsp?pageId=0996b43f802e36c4
https://shop.advanceautoparts.com/r/advice/car-maintenance/how-to-change-oil-filter
From Autozone "Partially filling the new filter with oil will reduce the time the engine must run dry when starting."
https://www.autozone.com/repairinfo/repairguide/repairGuideContent.jsp?pageId=0996b43f802e36c4
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Originally Posted by Zee09
What do you do if you have no oil filter?
Then you are probably driving a Volkswagen type 1, which only used an oil screen.
So do many aircraft engines.
So do most cars built before 1960 or so.
There's no worry about pouring new oil from a jug into the "clean" side of an oil filter.
What do you do if you have no oil filter?
Then you are probably driving a Volkswagen type 1, which only used an oil screen.
So do many aircraft engines.
So do most cars built before 1960 or so.
There's no worry about pouring new oil from a jug into the "clean" side of an oil filter.
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.
I can see you're really serious about this, so how is it okay then to not prefill the filter but turn around and pour 5 or 6 or 7 quarts of unfiltered oil directly into the engine? It's hard to believe that new oil could be that dirty, but if that's true, then filling your engine after an oil change has got to be even worse.
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.
I can see you're really serious about this, so how is it okay then to not prefill the filter but turn around and pour 5 or 6 or 7 quarts of unfiltered oil directly into the engine? It's hard to believe that new oil could be that dirty, but if that's true, then filling your engine after an oil change has got to be even worse.
gathermewool
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Originally Posted by IndyFan
A guy posts something stupid and we get 5 pages in his thread. Love da internet!
And now you've mastered the etherwebs. #blessed
A guy posts something stupid and we get 5 pages in his thread. Love da internet!
And now you've mastered the etherwebs. #blessed
Originally Posted by Big_3_Only
I can see you're really serious about this, so how is it okay then to not prefill the filter but turn around and pour 5 or 6 or 7 quarts of unfiltered oil directly into the engine? It's hard to believe that new oil could be that dirty, but if that's true, then filling your engine after an oil change has got to be even worse.
Pouring oil into the oil fill hole and having it drain down into the sump isn't the same as oil flowing throughout the entire oiling system from the oil pump. Pouring oil into the engine doesn't flow through the bearings, etc.
I have no problem pre-filling oil filters. I dont shake the bottle just in case any heavy stuff has settled out in the bottle.
I can see you're really serious about this, so how is it okay then to not prefill the filter but turn around and pour 5 or 6 or 7 quarts of unfiltered oil directly into the engine? It's hard to believe that new oil could be that dirty, but if that's true, then filling your engine after an oil change has got to be even worse.
Pouring oil into the oil fill hole and having it drain down into the sump isn't the same as oil flowing throughout the entire oiling system from the oil pump. Pouring oil into the engine doesn't flow through the bearings, etc.
I have no problem pre-filling oil filters. I dont shake the bottle just in case any heavy stuff has settled out in the bottle.
Originally Posted by ZeeOSix
Originally Posted by CT8
The oil filter will be in bypass until the oil pressure builds.
Why? Oil pressure "building" has nothing to do with the operation of the bypass valve.
I guess you are the expert on how an oil filter bypass works,
Originally Posted by CT8
The oil filter will be in bypass until the oil pressure builds.
Why? Oil pressure "building" has nothing to do with the operation of the bypass valve.
I guess you are the expert on how an oil filter bypass works,
Originally Posted by CT8
Originally Posted by ZeeOSix
Originally Posted by CT8
The oil filter will be in bypass until the oil pressure builds.
Why? Oil pressure "building" has nothing to do with the operation of the bypass valve.
I guess you are the expert on how an oil filter bypass works,
Please explain why you think a filter bypass opens up until oil pressure is achieved. I just want to know why you think that.
Originally Posted by ZeeOSix
Originally Posted by CT8
The oil filter will be in bypass until the oil pressure builds.
Why? Oil pressure "building" has nothing to do with the operation of the bypass valve.
I guess you are the expert on how an oil filter bypass works,
Please explain why you think a filter bypass opens up until oil pressure is achieved. I just want to know why you think that.
Been pre filling oil filters for 35 years and no harm done.
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