Pre-fill OF

[ZeeOSix]

At startup the oil is cold and has a high film thickness.

Only after the moving parts have gained enough speed to build an adequate MOFT. And when an engine is shutdown hot, the remaining oil film will be pretty small since it was fully hot (low viscosity) and will drain off as much as possible. If there is only the left over residual oil film inside the journal bearing without any new oil supply to the bearings, then it's hard to say if that remain oil film is giving full bearing protection or not for the first 4 or 5 seconds it may take to get fresh oil to them if the filter is installed dry and some galleries above it are also empty. The number of crank rotations in that short time period may only be around 50 revolutions, so even if there is some metal-to-metal contact it's going to be for a very short duration. Will it be noticeable wear over say 4,000+ start-ups in 200K miles (estimated) on the engine? It's a small sliver of all things that can cause engine wear so who knows for sure, but getting oil to the required parts ASAP is something positive IMO, regardless if doing so vs not can be detected from behind the wheel or not.

 

[dnewton3]

There has been no discussion so far about the TBC; the film barrier which exists on the surfaces as a result of oxidation. That plays a large part in reducing wear at startup as well. Yet many here are professing that a hydrodynamic barrier at startup is the only defense against start-up wear, and that's simply not true.

Additionally, how does this topic turn upside down, when the filters are upside down? IOW, the presumption here is that pre-filling an oil filter is a great idea and has a major benefit over not filling the filter. OK; if that's true, then how horrible it must be to have an oil filter that's "upside down" when installed and cannot be prefilled. Or, for that matter, what about cartridge filters; they can never be prefilled. Are we to assume that not pre-filling these engine filters is going to shorten the life or otherwise end up with a far less desirable wear trend, all because they were not pre-filled?

NEWS FLASH ... There are a LOT of engines that have filter orientations or designs which prevent pre-filling. If pre-filling were THAT important, if it were THAT able to reduce wear in a substantial manner, would not all OEMs make sure to have filter designs which are prefilled, and even mention it in the manual?


I call poppycock on the whole topic; it's moot.

 

[ZeeOSix]

If pre-filling were THAT important, if it were THAT able to reduce wear in a substantial manner, would not all OEMs make sure to have filter's prefilled, and even mention it in the manual?

They would most like all have a pre-lubing oiling system that operated before the engine fires up.

 

[vpr5703]

Without doing an in-depth analysis of 2 engines in a controlled test, all of this is postulation anyhow. And even then could you really control the conditions well enough to measure minute amounts of wear on the bearings and other surfaces?

The best case scenario is you're reducing wear within the engine. The worst case scenario (assuming the oil pump primes itself correctly) is that you're wasting time.

 

[350Rocket]

I've prefilled a couple of times with vehicles that have allowed me to. For the most part I noticed no decrease in the amount of time the oil pressure gauge or light has indicated a lack of oil pressure so I chalked it up as a waste of time on any filter that doesn't require a ton of oil to actually fill.

Not to mention I'm in the rust belt, things tend to rust out before wearing out around here. Never had any engine issues and I've had a couple of my engines a part with no indication of bearing wear.

If splash lubes engines and lawn mowers can last 100's of hours and many thousands of miles while being splash lubed, the residual oil in the bearings can protect them for 2 seconds while the filter gets filled.

The myth about fresh oil being dirty before going through the filter was very recently disproven so I will be going back to pre filling every time like I used to (before this crazy place put doubts in my head).
I usually did it when I worked in an express lube, one vehicle that proved to me that it was worth it was the gm ecotec. Every one of them rattled on startup until I started pouring oil into the cartridge filter media before putting the new filter in. Doing that made them start up nice and quiet. Will they last a while without? Sure they will, but definitely they will last longer if you do pre fill.

 

[wemay]

Never

 

[350Rocket]

They would most like all have a pre-lubing oiling system that operated before the engine fires up.

And why would they care if they lasted that much longer? Oh yeah, they wouldn't. They want us to buy a new one eventually.

 

[twX]

When looking at at least Subaru oil pumps and especially with “normal” filter sizes, once the crank is spinning it’s pumping significantly more volume than the canister can hold… I.e., likely before the engine even fires and begins to run, the filter itself is full.

On my Subaru, if the car has been sitting for hours before starting, the oil pressure light only shuts off maybe half a second after the engine reaches cold idle rpm. If I use flood mode to crank the engine, it takes over 5 seconds for the light to go off. After an oil and filter change it can take over 15 seconds of cranking.

If the engine has been run in the last 15 minutes or so, the light goes off almost immediately upon cranking. I'm not sure if this difference has to do with the ADBV on the oil filter, but this is with a slightly oversized FRAM Ultra with a silicone ADBV. Maybe some oil slowly drains out of the journal bearings over time.

 

[350Rocket]

Without doing an in-depth analysis of 2 engines in a controlled test, all of this is postulation anyhow. And even then could you really control the conditions well enough to measure minute amounts of wear on the bearings and other surfaces?

The best case scenario is you're reducing wear within the engine. The worst case scenario (assuming the oil pump primes itself correctly) is that you're wasting time.

Yes but very little time. If you're on this site, then you care a lot about taking the BEST care of your equipment. So why would you not care?

 

[ZeeOSix]

And why would they care if they lasted that much longer? Oh yeah, they wouldn't. They want us to buy a new one eventually.

Read what comment I was responding to. dnewton said if it was that important to pre-fill, then I replied all engines would probably have pre-lubing systems (meaning if it was that important/critical). Context matters.

 

[ZeeOSix]

On my Subaru, if the car has been sitting for hours before starting, the oil pressure light only shuts off maybe half a second after the engine reaches cold idle rpm. If I use flood mode to crank the engine, it takes over 5 seconds for the light to go off. After an oil and filter change it can take over 15 seconds of cranking.

If the engine has been run in the last 15 minutes or so, the light goes off almost immediately upon cranking. I'm not sure if this difference has to do with the ADBV on the oil filter, but this is with a slightly oversized FRAM Ultra with a silicone ADBV. Maybe some oil slowly drains out of the journal bearings over time.

Is that one of the engines that Baxter came up with a system to keep oil from draining out of the oiling system?

 

[twX]

Is that one of the engines that Baxter came up with a system to keep oil from draining out of the oiling system?

Yeah, I see that Baxter has an explanation for why it happens here.

 

[350Rocket]

Read what comment I was responding to. dnewton said if it was that important to pre-fill, then I replied all engines would probably have pre-lubing systems (meaning if it was that important/critical). Context matters.

Sorry, my comment was mainly to him, in addition to your comment.

 

[Fishstyx]

Beat me to it. I don’t pre-fill because I own a Subaru and you have to flood start it to circulate the oil through the engine and filter before you start it regularly.

 

[nomas]

I will continue to pre-fill whenever possible . I don't need to debate it with anybody . Carry on ...

 

[ZeeOSix]

I'm looking for the member here that showed a video of a clear oil filter he built. If I recall correctly, in one of his videos he cranked the engine with the clear oil filter dry, and it showed how the filter filled up with oil as the engine cranked. It took a while for the filter to fill up. Engine cranking RPM is going to be way less than fired up RPM, and most engines will fire-up with little cranking. In either case, since it's a positive displacement oil pump, the engine will rotate X revolutions before full oil distribution and pressure is obtained.

Here's another video showing how long it took to fill the filter by just cranking the engine without it firing. Cranking RPM being much slower than running RPM at idle naturally takes longer in time. I don't think the filter's ADBV is working properly in their modified clear filter - that's why the air pocket appears in the top of the filter after the engine is shut-off. Not the video was referring to, still looking for that one.

 

[ZeeOSix]

Here's the one I was originally referring to - the whole thread.

I Built a See Through Oil Filter

I took laboratory beakers and bonded them to the head of 4 Purolator filters in various configurations to illustrate how oil flows through a filter assembly. The fuel pump fuse was removed so that the engine couldn't start and develop full oil pressure to blow up the glass beakers. I just...

bobistheoilguy.com