When I change my oil, first the plug gets pulled, then the filter. I wipe the gasket seating area off, the using CLEAN oil I lube the gasket, fill the oil filter ONLY if it's a straight shot to the spud it screw's onto. No sense having the oil draining down your arm ,or side of the filter . Tighten the filter hand tight, then Put the plug back in, and fill'er up. I've been doing this routine since I got my first car in 1971. They say most engine wear happens at startup. I kinda think it's due to starting a motor with no actual oil being circulated , while waiting for the filter to fill, then get circulated inside the motor. When you shut your motor off after running , isn't your filter full of oil?, and doesn't your oil pressure read just about instantly on the next startup?. So how could that be a bad thing?.,,
This guy says pre-filling an oil filter is bad and that all manufacturers say so.
- Thread starter atikovi
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EXACTLY.
The risk of a new jug off the shelf being contaminated is low, but it happens, a piece of foil, a bit of plastic, something from the line, or the occasional return disguised as new may not be caught.
Oil dumped in the fill hole will work its way to the sump and get filtered before going to the bearings
a pre fill bypasses the filter sending it directly into the engine unfiltered.
If you study fleet practices or spend some time on the machinery lubrication site you'll find that the cleanest plants will pre filter ALL lubricant before dispensing. Some fleet managers will tell you the factory barrel or jug cleanliness ratings are rarely met.
Whats the risk - low, but there is risk.
To me, the plus side of this defeats the minus side. Prefilling the oil filter every time you change oil, provides all but instant oil pressure. Which is a good thing.
The only minus is the possibility of you somehow introducing some type of contaminate into the whole oil change process by prefilling your new oil filter. I don't know anyone who has ever filtered their new oil straight from the jug, before introducing it into the engine.
The only minus is the possibility of you somehow introducing some type of contaminate into the whole oil change process by prefilling your new oil filter. I don't know anyone who has ever filtered their new oil straight from the jug, before introducing it into the engine.
There is nothing inherently wrong with pre-filling a filter. I always did on diesels that used a spin on filter. That being said there are millions of cars on the road that have never had a filter pre-filled with hundreds of thousands of miles on them with no issues from not pre-filling.
No it does not! Not sure where you ever thought that?
Please state a reference to your statement regarding this comment?
At one time when I built engines (for a living) I thought that if I pre filled the oil filter it would save time in manually priming the oil pump and getting oil pressure for prior to starting a newly *"built" engine . NOPE!!!! Waste of time and increases the chance of spilling and needing clean up the mess.
*Having a "built" motor means you have replaced some or all of the factory components with upgraded aftermarket ones. ... This is where taking shortcuts will lead you to failure | A proper built motor will have the entire rotating assembly upgraded. This includes crankshaft, rods, and bearings in addition to the pistons.
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Not if you're one of picky OCD people that has devised a way to hold open the ADBV, while you pour the oil into the filter past the held-open ADBV, thereby ensuring even the fresh oil from the bottle goes through the filter media, before entering the engine.
I'll rephrase it. Prefilling the oil filter produces oil pressure far FASTER than installing a dry filter does.
If you are "that guy" then you have almost no risk from contamination.
No it does not. Please show me any empirical DATA that states this? OR are you and engine builder by profession at any time and have tested you interesting comment because I am and have!
Your idea was discussed in a lengthy thread we had here back in 2004:https://bobistheoilguy.com/forums/threads/pictures-of-whats-in-new-oil.8308/ Unfortunately, the stunning particle count pictures are gone. Maybe things are different regarding oil cleanliness 17 years later?
Thread starter member Stinky Peterson (RIP) operated a CAT oil anaysis lab and his personal opinion was that pre filling filters had more risk vs. benefit.
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Duplicate deleted. Sorry.
Thanks
Machinery lubrication has a couple articles that discuss this.
As an older guy I've absorbed tons of articles on this over the years pro and con.
Seems like it rarely to never hurts, but doenst seem to buy you anything regardless.
My largest filter happens to be a cat 3126 filter and dont do it I never once heard any irregular clatter on startup.
Thanks for the explanation. Does it go into the pan first, then the filter, then the engine?
Sounds like a new patented device needs to be marketed.
I've measured the time it takes for oil pressure to build on first start-up after an oil and filter change. Time with no filter pre-filling was 5-6 sec and time with the filter pre-filled filter was 2-3 seconds. May not make any difference to the engine, but the difference can be seen on first start-up so I continue to pre-fill.
Yes, flow path is: Sump ---> Oil Pump ---> Oil Filter ---> Engine Oiling System ---> Back to Sump.
How long does it take after the vehicle sits overnight or longer? Do things like the pickup tube drain out, causing longer times? Just asking.
After an oil change, I "think" (don't know) there is plenty of lube left over on parts to make pre filter filling a non issue (just my opinion). If one keeps their car for 200k with 6K OCI's, that's 33 starting events. My opinion is pre filling will not make a difference.
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Completely different topic from the one being discussed. This is about prefilling the filter during an oil change, not about during the first startup of a rebuilt engine that is dry internally.
Sounds like a new patented device needs to be marketed.
Nah, it would just be immediately copied by someone in China, who couldn't care less about patents.
