At least I understand how a K&N airfilter is cleanable - wash out the oil and the contaminants that have stuck to the oil, put in clean oil. Can’t do that with an oil filter…
The K&N reusables are stainless steel mesh or something like that. So that’s how they get cleaned.
SS mesh? Sounds like it’ll let gravel through…
Seriously, any mesh fine enough to trap what a paper element would trap would either clog immediately or be almost impossible to clean. A dangerous waste of money.
Well they call it a “dual woven T 304 stainless steel micro-screen” - I suppose that might be meaningful to someone. Wouldn’t you know - they also sell filter cleaner. But mostly the instructions say it’s best cleaned in a parts washer.
There’s a basic description here: http://www.knfilters.com/oilfilter.htm
I was just about to post that link. It’s very hard for me to believe that woven SS can catch anything close to what a paper filter can. Of course they push the “low-restriction” angle, like that would be some source of power…
They have good marketing people. Creative little buggers…
My understanding of K&Ns air filters goes back 10 years to when we did some engine analysis of them on a dyno.
Most know that traditional paper elements filter the air by forcing it thru the pores in the paper. The larger dirt gets caught while the air molecules fit thru the pores.
K&N use a different technique. Their filters are constructed like an open cell sponge; lots of little internal compartments, all interconnected. The walls of these cells get coated by the filter oil that is required. The air is then forced to move thru this maze of compartments, and in doing so most of the air ends up hitting a wall or two on the way, to which the dirt in the air sticks because of the sticky oil residing there.
Because there are no ultra-small pores like in the paper filters, the air is more “free flowing.” Thus the claim of great air flow/ more engine power. Problem is, there is no guaranty that all the dirt will hit the walls and stick. Some of it can and does flow with the air around the cell walls, all the way into your engine.
If you think your engine will actually gain horsepower from a free flow air filter, there is a simple test. Take the filter element out altogether, and do a test drive (preferably not on a dusty day). If you can’t feel any power gain, then no filter in the world will make any difference.
Excellent description Tony. And good quick test.
Air for the engine is like water for the body. If you need a gallon a day to be healthy, and your supply is capable of giving you a gallon and a half, than a supply that can provide two gallons a day does nothing for your health. Greater airflow capacity can only help if the current capacity is insufficient for the engine’s needs.
Re: the particulate size and the amount that gets through, I contend that filtration of smaller particle sizes only matters if the particle size being allowed through is large enough to affect engine performance and/or wear.
I could be wrong, but I seriously doubt of any modern engine’s filter has less than sufficient capacity or filtration. I’ll bet the exact opposite.
Re: K&N’s “cold air intakes”, when I looked into them I discovered that they drew the air from exactly the same locations as stock intake snorkles. How could the air be colder? K&N has used the fact that cooler air is denser and does contribute to power to advertise their intake… which doesn’t actually provide cooler air at all! I also became aware that their oiled filters can allow fumes to coat the mass airflow sensors, rendering their signals incorrect, but that’s another story.
Kudos to K&N’s marketing department. But my personal opinion is that they dance on the very edge of deception.
Tom and Ray's home state requires that anyone selling motor oil must also take back used oil.
We have the same thing in NH. But it’s NOT like the bottle law where they actually give you money back. It’s that the retailers have to take your used oil. For some people that’s still an inconvenience. I’ve seen a guy at a self server car wash do an oil change in one of the bays. He didn’t have a pan to catch the oil…just dumped it in the bay down the drain. When finished he washed his car and when on his way.
If you’re crafty you can do a lot better than free…I’m currrntly getting $1/gal for the stuff. It’s my love of things green that keeps me compliant.
Anyways, assuming the reusable oil filter is chosen for ecological reasons…it’s “I don’t want to expose fish to dilute used motor oil–so I’ll expose myself to full-strength oil AND toluene?!?”
One’s heart is in the right place…one’s head, however…
I just looked at the K&N re-usable oil filter for my Camry, $220. All I can say is WTF! I could easily buy about 6 years worth of Toyota OEM for filters for that ! !
To the OP I would put that $220 to finding and fixing the vibration problem.
Here’s a simple test for an oiled gauze filter (like K&N): shine a light through it.
You’ll see pin holes. Pretty much assured SOME sizable dirt will get through that.
One way to measure the effect of air restriction is to use an OBDII scanner and measure the MAF or MAP data at wide open throttle near redline, with and without the filter.
Was it AMSOIL that had a remote canister which used rolls of toilet paper for the filter element? I hated the canister with removable filter elements used on 1950s and older vehicles when I worked at a service station. What a mess! I remember installing a spin on filter adapter on my 1955 Chevrolet for about $5. Even though that was about 1.25 tanks of gas at the time it was well worth it.
Oh, Lordy, I remember those from the early '70s, perhaps earlier. I don’t even know if AMSOIL was in business back then. That is on my list as one of the dumbest ideas I’ve ever heard, totally devoid of any common sense whatsoever.
I’m not a fan of the new removable element oil filters, but I suspect they’ll be very common very soon. I think I’ll keep my current car for at least fifty more years.
Paying $220 to “save” money in the long run . . . ha ha ha
The idea that the K&N filter will do a better job than the factory filter . . . ha ha ha
Toyota could easily have designed the engine to use a cartridge filter, had they wanted to do so
Clearly, they felt it wasn’t necessary
@sgtrock, that was Frantz that manufactured those remote toilet paper oil filters and they’re still around today.
One of those things was given to me many years ago for use on an old VW Beetle and I just never had the intestinal fortitude to try it. The thought of TP clumping up and the fact that most of the circulating oil doesn’t even go through the TP kept me from ever using it.
There was an oil-soaked roll of TP in that unit when I got it and it was very, very discouraging to look at.
Eventually I threw it on eBay and it sold for 50 bucks; go figure.
LOL
I find the use of the term “intestinal fortitude” in describing your reluctance to use a toilet paper filter hysterical. Thanks for the laugh.
@ok4450 Frantz sounds familiar as the manufacturer. I researched and AMSOIL/Frantz are still in business! AMSOIL is known as the AMWAY of automotive products. I found this comment on a Cummins Diesel forum. Re: Frantz toilet paper oil filter… anybody use them?
When I worked at a Dodge dealer back in 62, we had a guy that would come in with an old Plymouth wagon, pay a buck and a half for a lube job and while you were working on his car he would change the toilet paper filter on his car, make a mess and never tip you. It was a Franz filter and the car had a Perkins diesel engine. I asked a Shell engineer about that and he said " Would you drink from a dirty toilet"? and I said no, then he asked " If I ran the contents through that filter till it showed perfectly clear, would you drink it then "? again I said no !. " he asked why ? and I said all you have done is taken all the particulates out but the liquid (urine) is still there. He said “Exactly, the filter takes out the particulates but the acids and contaminates that build up in the oil are still there, that is why you change the oil”. Look at lead deposits under the sludge in a oil pan and the pits in bearing surfaces. They were not ground in by dirt they were eroded by acids. Don’t need to say more.
Take Care and oil is cheap insurance, Old Navy
@thesamemountainbike, just a lame pun thrown into the mix. 
Even lamer are those TP filters. I simply cannot believe they do one bit of good. It’s claimed that most of the oil bypasses the TP and what little that does go through the TP filter probably goes around the ends of the TP.
Wonder how they compensate for those varying and narrower width rolls…
The TP that I’ve seen come out of those things was nothing but an oily blob of Play-Doh and I certainly don’t see much if any oil passing through countless sheets of mucked up TP. If oil did not bypass the TP then odds are there would be a lot of seized engines.
Their technical explanation leaves a lot to be desired also…
Anyhoo, wipe the slate clean and roll on to other thngs…
I’ve never actually seen one. A used roll I mean. I mean used as a filter. I mean to filter oil.
Oh crap! Never mind.