K&N Filter Cleaning Frequency?

[TexasViper35]

I was thinking about cleaning my K&N filter but I decided to search to see just how often it’s supposed to be done. The K&N website says 50K miles! What? Is that for all applications including a Viper, or other more basic types of vehicles? The site says that the dirty filter actually filters better. Any input would be appreciated.

On a side note, I read that the Demon came from the factory with a K&N filter.

 

[steve e]

I have K&N filters in all my cars, go by how it looks, if its looking dark and dirty clean it and re oil, there really is no set time, it depends on where and how the car is driven, a few off road blasts in the Jeep and its time for a cleaning, the Viper can go a long time if only driven on the street, track time kills the filter, you can not hurt anything by keeping a clean air filter.

 

[kssssnake]

My two cents worth. Do not clean the filter. Throw it away. I cleaned one once. Either I screwed up or re-oiling is not a controlled process. Shortly after I re-oiled it the performance went down. This was not in a Viper. It appears that the excess oil flows down stream and gets on the mass air flow sensor. Cleaning one is not fun. Small dust particles accumulate on the resistor and thermistor causing false feedback and bad performance. On this vehicle the sensor is within inches of the filter. On a Viper it is further away. That said, K&N filters are supposedly less restrictive which implies that more dirt gets through which is not a good thing. Yes a dirty filter does filter better. That's a good thing for a swimming pool, not a Viper. Oh, avoid driving in dusty locations. If you find yourself in a dusty spot get out of the throttle, hit the clutch and roll through the dust cloud to avoid sucking the cloud into your filter engine.

 

[TexasViper35]

I think I will buy a new set the next time, its time consuming to clean these things! Drying alone takes 3-4 hours on a hot day or overnight, oiling all of the pleats is a pain on the fingers and the eyes, it’s just not worth the trouble.

 

[steve e]

Yea Ksssnake is right, on my Viper and Shelby I just buy a new one not worth the effort , but on my jeep I clean it , I would be buying new filters monthly.

 

[Frank Parise]

I've always used them on my Vipers without any issues whatsoever. I inspect them on every oil change, and use judgment as to whether a cleaning and re-oiling is necessary.

 

[kssssnake]

The issue I had was on a '95 mustang GT. The sensor is inches from the filter. The filter let enough trash through that it was visibly built up on the components which are about a mm in diameter and a few mm's long on wires about the thickness of a hair. I'm not convinced that K&N filters are as effective as stock filters. Cleaning after disassembly was with electronics cleaner and a tooth pick. Got a visible fuzz ball off of each component. On a 250HP car it's not worth the gain. Stock filter works fine.

 

[TexasViper35]

How would you know that the K&N was responsible? Unless the car came with a K&N new from the factory there’s really no way to tell. I would tend to believe the K&N is a superior filter to paper.

I’ve read tons of comments by people about the oil contaminating the MAF, but K&N was reading too. They proved, scientifically, that all the rumors were just a myth. They over oiled a filter and ran air through it at 1000 CFM, no oil came off. You can find the two (2) research articles on their website.

They sell maybe 25 million of these a year, there would have been class action lawsuits like mad if any of the myths were actually true.

 

[Frank Parise]

I'm not aware of anyone in the Viper Racing League ever using something other than K&N. As I recall, all GEN 2 ACR Vipers came from the factory with K&N.

 

[MoparMap]

I remember Dick Winkles saying something along the lines of the cloth style filters offered no noticeable difference on a stock engine, but that's just it, a "stock" engine. The engineers developed the whole setup and tested a bunch of different options, I can guarantee that.

However, once you start changing things is where the water gets murkier. I have no doubt that a stock paper filter flows exactly as much as it needs to flow for a totally unmodified car and that a fiber filter likely offers no real benefit. However, start changing cams and porting heads and swapping exhaust or basically anything that affects air flow through the engine and that equation starts changing. The paper filter probably has a little overhead and excess flow built in, but maybe not a ton.

Generally speaking though, if you don't change the area at all but are now able to flow more air, that basically means you have less restriction, and with less restriction I would bet you probably actually have less filtering. Just kinda the way things work. Whether that's a problem for you is up to you to decide.

 

[TexasViper35]

What if the filtering efficiency is exactly the same? These are two different filter medias, multiple layers of cotton gauze soaked in oil versus compressed fibers (paper), so they use two different principles to capture dirt and dust. That doesn’t absolutely mean that one is more efficient at filtering than the other. It more likely means that one is more efficient at air flow while maintaining the same filtering coefficient.

I’ve read way too much about this subject. But =/>5 microns seems to be the target size and K&N grabs them. For reference, a human hair is 50 microns and the human eye cannot see anything smaller than 40 microns. K&N has an efficiency of 97-99%. 99% is going to be the maximum on any filter system.

 

[InTheZoneAC]

I have K&N filters in all my cars, go by how it looks, if its looking dark and dirty clean it and re oil, there really is no set time, it depends on where and how the car is driven, a few off road blasts in the Jeep and its time for a cleaning, the Viper can go a long time if only driven on the street, track time kills the filter, you can not hurt anything by keeping a clean air filter.

This.

When cleaning just spray the outside with a cleaner, properly rinse out by directing water to the inside. Do not directly rinse the outside of the filter.

Then what i do is take a little box, lay it sideways, put the filter in it with the inlet facing out, direct a fan (nothing powerful) right at It for 15 minutes to dry it out.

The filter should be almost white if it's properly cleaned instead of black like when it was dirty. After drying gently tap the filter sideways against your hand or arm and make sure no excess water is coming out of the paper/mesh.

When applying oil you don't need to drown it. Just apply a light coat in even strokes. I'll start spraying off the filter then run it over the filter so no excess builds up on either side. A faint red is too light, apply another coat if it is. Don't need it to be bold red as that's just restricting the breathability of the filter.

Then I take another 5-10 minutes to dry the filter in the cardboard box again. If you're getting any oil inside the intake pipes then you failed to let it dry or over-oiled by a massive amount. If you find an even layer of dust inside the intake pipe then it was either dry or under-oiled.

 

[InTheZoneAC]

I think I will buy a new set the next time, its time consuming to clean these things! Drying alone takes 3-4 hours on a hot day or overnight, oiling all of the pleats is a pain on the fingers and the eyes, it’s just not worth the trouble.

proper drying takes no more than 30 minutes, this is including cleaning and oiling. Read my post before this for how I speed up the drying process.

 

[TexasViper35]

proper drying takes no more than 30 minutes, this is including cleaning and oiling. Read my post before this for how I speed up the drying process.

I’m in Dallas; it’s been roughly 90°F in the mid to late mornings lately. It literally took 3.5 hours for both filters to fully dry, including residual condensation inside, while sitting in the heat of the morning sun. The best way is just to set them aside overnight, but that’s not always an option. If you were to oil them while they were still somewhat [imperceptibly] damp, the oil would be prevented from fully wicking into all of the filter material, resulting in the white or light red areas that you mentioned. On that same note, K&N recommends allowing the oil to wick for twenty (20) minutes.

I just follow the manufacturer instructions, pretty simple, here:

https://www.knfilters.com/instructions/18627B_inst.pdf

ETA I just reread your post. No offense intended at all, but there is no possible way that your filter was anywhere near dry enough to be oiled, you oiled a water soaked filter. That is based off of the time you allowed and your visual description of the filter as you tried to add the oil. It most definitely should have been a consistent dark red color all over, inside and out.

K&N filters have between four (4) to six (6) layers of cotton fabric. Imagine four (4) wet cotton t-shirts layered atop each other, pleated up, and then left to dry in a box with a small fan for only fifteen (15) minutes; impossible. Maybe next time give it a try after letting the filter dry overnight and compare your results. I think you will be pleasantly surprised at what happens when you apply the oil.

 

[InTheZoneAC]

I’m in Dallas; it’s been roughly 90°F in the mid to late mornings lately. It literally took 3.5 hours for both filters to fully dry, including residual condensation inside, while sitting in the heat of the morning sun. The best way is just to set them aside overnight, but that’s not always an option. If you were to oil them while they were still somewhat [imperceptibly] damp, the oil would be prevented from fully wicking into all of the filter material, resulting in the white or light red areas that you mentioned. On that same note, K&N recommends allowing the oil to wick for twenty (20) minutes.

I just follow the manufacturer instructions, pretty simple, here:

https://www.knfilters.com/instructions/18627B_inst.pdf

ETA I just reread your post. No offense intended at all, but there is no possible way that your filter was anywhere near dry enough to be oiled, you oiled a water soaked filter. That is based off of the time you allowed and your visual description of the filter as you tried to add the oil. It most definitely should have been a consistent dark red color all over, inside and out.

K&N filters have between four (4) to six (6) layers of cotton fabric. Imagine four (4) wet cotton t-shirts layered atop each other, pleated up, and then left to dry in a box with a small fan for only fifteen (15) minutes; impossible. Maybe next time give it a try after letting the filter dry overnight and compare your results. I think you will be pleasantly surprised at what happens when you apply the oil.

drying is not a "visual inspection". The box method inside your house rapidly speeds up the drying, why would anyone rely on drying in humid temps and have to deal with dew and condensation?. If you want to talk humidity come to eastern NC where humidity puts to shame whatever you have in Texas. I stated several tests indicating if you have sufficient oiling or not. By all means keep oiling your filter where it's bleeding through the inside.

I read those instructions, it pretty much stated what I stated, but I improvised with a more efficient and faster way to dry. Think of my drying method as drying the car off with a small electric air duster vs letting it sit out and waiting for the water to evaporate.

edit: If my method doesn't allow it to properly dry then I would visually see blotches or shades of uneven oil across the filter after it did dry. I would also get some bleed through. I'm not trying to argue with you, just stating basic principles of what would actually happen if I was doing something wrong.

As stated in my original post if I didn't apply enough oil then I would have dust settle on the inside of the filter, especially around the neck before it attaches to the pipe and along the first several inches of the pipe. Too much oil and it would bleed through and you'd get runs along the inside of the filter and pipe. Any amount of oil in-between too much and too little is fine. One just allows slightly more airflow, which in turn will slightly lower your gas mileage (most likely you won't notice the difference)

 

[TexasViper35]

drying is not a "visual inspection". The box method inside your house rapidly speeds up the drying, why would anyone rely on drying in humid temps and have to deal with dew and condensation?. If you want to talk humidity come to eastern NC where humidity puts to shame whatever you have in Texas. I stated several tests indicating if you have sufficient oiling or not. By all means keep oiling your filter where it's bleeding through the inside.

I read those instructions, it pretty much stated what I stated, but I improvised with a more efficient and faster way to dry. Think of my drying method as drying the car off with a small electric air duster vs letting it sit out and waiting for the water to evaporate.

edit: If my method doesn't allow it to properly dry then I would visually see blotches or shades of uneven oil across the filter after it did dry. I would also get some bleed through. I'm not trying to argue with you, just stating basic principles of what would actually happen if I was doing something wrong.

As stated in my original post if I didn't apply enough oil then I would have dust settle on the inside of the filter, especially around the neck before it attaches to the pipe and along the first several inches of the pipe. Too much oil and it would bleed through and you'd get runs along the inside of the filter and pipe. Any amount of oil in-between too much and too little is fine. One just allows slightly more airflow, which in turn will slightly lower your gas mileage (most likely you won't notice the difference)

Do whatever you like. People here don’t tend to be rude or confrontational, I am no exception. But simply put, in the nicest way possible and with respect, you are completely wrong about basically everything on this topic. If you were to contact K&N, which I did, they will tell you that it takes at least four (4) hours for their filter media to dry after a cleaning, and putting it outside with the added heat from the sun is an enhancement. Dallas is nowhere near water, it is not the least bit humid; it’s completely dry and it’s really freakin’ hot (100°+) in the summer afternoons. The inside of the filter dries the slowest, so if you check and find that it’s inner wire mesh is wet (condensation via evaporation) then the filter needs more time to dry. A completely dry filter accepts the oil readily from the top of the exterior pleats, and in a uniform fashion with a uniform color all over. If I were to ever over oil a filter to the point that it was “bleeding” on the inside mesh I would just start all over again.

 

[InTheZoneAC]

Do whatever you like. People here don’t tend to be rude or confrontational, I am no exception. But simply put, in the nicest way possible and with respect, you are completely wrong about basically everything on this topic. If you were to contact K&N, which I did, they will tell you that it takes at least four (4) hours for their filter media to dry after a cleaning, and putting it outside with the added heat from the sun is an enhancement. Dallas is nowhere near water, it is not the least bit humid; it’s completely dry and it’s really freakin’ hot (100°+) in the summer afternoons. The inside of the filter dries the slowest, so if you check and find that it’s inner wire mesh is wet (condensation via evaporation) then the filter needs more time to dry. A completely dry filter accepts the oil readily from the top of the exterior pleats, and in a uniform fashion with a uniform color all over. If I were to ever over oil a filter to the point that it was “bleeding” on the inside mesh I would just start all over again.

I'm done responding to you after this. Instead of questioning what I'm saying try to actually visualize what I wrote in my step for step. Stop, right there stop. Again, try to understand what I wrote before questioning every little detail. Stop! I already see you trying again.

-My drying method involves pointing the fan at the inside of the filter (you say the inside dries the slowest, I've already covered this). The box method allows more air to circulate in and out of the filter....which contributes to a faster drying process.
-My drying method involves drying inside (you mention it's hot in Texas, I don't care, that's irrelevant. Drying outside allows any dust or debris to settle on or in the filter)
-I don't care what K&N says about drying the filter media because my method speeds up the process. Why do something that takes longer for the EXACT SAME result? If you want to justify spending 4 hours on something when it takes me 30 minutes, then by all means waste your time.

There's more than one way to tackle any job and I provided a detailed explanation of what I do. I don't need someone to come in here and claim that every detail is wrong when I have proven with my owns results that it's not. And I also provided more details on how to "fact check" my own method.

If you still hang your clothes out to dry vs using a drier no one's going to say what you're doing is wrong, but I am going to question why you choose that over the drier (if you have both means available to you). Have a good day.

 

[steve e]

All I have to say about drying time is it depends where you are, here in Prescott AZ its very dry and sunny and everything from K&N filters to vacuum cleaner filters are dry in 30 min or less, been here a long time and dried lots of stuff, when I was back east in NJ things would take for ever to dry,and forget about drying anything out side, it would be damp for days , bottom line why argue on dry time, let it dry after cleaning, how long it takes depends and is a none issue, as long as its dry when you oil it. I am going to try the fan method next that would be even faster, or even a hair drier would work, but like I said here where I live everything drys fast. Just my to cents

 

[steve e]

I all most forgot one more important step in drying, if you hold the filter on one end swing the filter downward, if done right you can get most of the water out just through centrifugal force, after 10 or 15 fast swings its pretty dry. I know not dry enough to oil but greatly speeds dry time. I did not read all the posts so if it was already mentioned to bad.

 

[InTheZoneAC]

I all most forgot one more important step in drying, if you hold the filter on one end swing the filter downward, if done right you can get most of the water out just through centrifugal force, after 10 or 15 fast swings its pretty dry. I know not dry enough to oil but greatly speeds dry time. I did not read all the posts so if it was already mentioned to bad.

Correct, swinging it and/or gently tapping it against your hand or against a towel will force some more of that stubborn water out. The fan just finishes up whatever was left.

 

[Big E]

I'm lazy. I bought extra filters so they'll be ready to go in at a moments notice. Then the dirty one gets cleaned and I wait a few weeks or so until dry. Then oil it and put it up so the oil wicks out and I'm ready for the next filter change.