SAE reports on air cleaner service life and engine wear

Fillherup · Mar 2, 2003

Joee12,

I would suspect that as a filter get a higher pressure drop other leaks around PCVs, hoses, etc start to play a bigger role in letting in air. So this might be a practical limiting factor on the life of an air filer beyond just a lab test.

I think someone else even suggested that more air input is outside of the filter. Maybe at the end of service life of an air filter for an average car, he is right.

On my car, I just repaced some rubber air parts. I did find a crack in a PCV hose on a 95 Carmy with 68K miles.

Americanflag · Mar 4, 2003

What you mention about the filter getting very dirty and then drawing in more dirt, I have heard K&N mention this as an advantage to their filters over paper. Just trying to stick up for K&N a little!

Greaser · Mar 4, 2003

quote:

Originally posted by Americanflag:
What you mention about the filter getting very dirty and then drawing in more dirt, I have heard K&N mention this as an advantage to their filters over paper. Just trying to stick up for K&N a little!

May-be they should start selling "pre-dirtied" air filters to improve reliability of their product

...Hey don't worry about it..just read the paper to-day and the Canadian government is tabling a bill to make aftermarket auto accessories ILLEGAL...in other words changing anything that was not OEM an offense!Nitrous was on the top of the list,along with aftermarket super/turbo charging systems...what next

nick778 · Mar 6, 2003

Some years ago I bought K&N filters to install on a Nissan 300ZX TT and a Volvo Wagon. Oil for both was Mobil 1 synthetic and never became ral dirty or black during or at the end of an oil change interval. Within 1500 miles on, the oil was very dark on both vehicles and the throttle bodies were very dirty (I clean them every oil change). I tossed the K&N and have used OEM filters ever since and change them when they look dirty or once/yr whichever is sooner.
IMO, I will take and prefer a slightly inefficient new OEM filter for the increased air flow and mpg reasons than to leave it in until it gets 'dirty' and 'optimally' efficient in filtering. The OEM filters, even new, are way more effective at filtering than i.e., a K&N based upon my experience.
On my Kawasaki 1500 Vulcan, I do have a K&N Thunder air intake but use a nylon prefilter on it as I can't locate a replacement paper filter.

Americanflag · Mar 7, 2003

Greaser, regarding your post on the Jeep and the off roading with the K&N, you mention a disadvantage of the K&N is that it draws water in more easily than paper.

K&N makes a filter cover for those doing off roading, that keeps water from getting in. Have you been using this?

OneQuartLow · Mar 7, 2003

If hydrolocked because of a K&N then it's probably just the worst of several bad things. Axles, ECU, ignition, transmission & tcase breathers, etc.

David

Greaser · Mar 7, 2003

quote:

Originally posted by Americanflag:
Greaser, regarding your post on the Jeep and the off roading with the K&N, you mention a disadvantage of the K&N is that it draws water in more easily than paper.

K&N makes a filter cover for those doing off roading, that keeps water from getting in. Have you been using this?

What are the stats on air flow the K&N with the pre-wrap installed?Thats what they reccommend in dusty conditions.Don't you think once they have you with their expensive filter kit installed now they are going to sell you more stuff..like pre-wraps and shorter run times..so you buy more cleaner and oil from them...does marketing come into effect here...I use paper and leave the hype to the other people...whats the real HP gains?From every test I've read it actually went down or stayed the same anyways

Greaser · Mar 7, 2003

quote:

Originally posted by OneQuartLow:
If hydrolocked because of a K&N then it's probably just the worst of several bad things. Axles, ECU, ignition, transmission & tcase breathers, etc.

David

Yes hydro-lodk is definately the worst thing that can happen..especially at high rpm's...axles can be drained and filled,ECU.ignition can be switched,the breathers for the axles are in the same catagory as the diffs...hey..use what you want....just putting a little info out there for comparative conjecture.I'll try and find the pics of the dudes Jeep that hydro-locked...shows his rods in pieces

OneQuartLow · Mar 7, 2003

Gotcha. Just trying to convey that the total cost of a new trans, radiator, fan, ECU, etc is roughly that of another engine. Lots of things to sweat before a paper filter completes the amphibious conversion.

S2000driver · Mar 7, 2003

So a K&N filter has to get dirty to filter efficiently. I expect most people clean theirs as soon as they get to this point.

The difference in filter media area between a paper/fiber filter and an oiled one is staggering! This means to me that the oiled filter will get dirty more quickly than a paper/fiber one with the larger flow area, because the same volume of air is passing through a smaller area. This would be another reason a K&N filter needs cleaned more often than the OEM change interval. Leading to more wear!

Bootlegger · Mar 7, 2003

After reading all this I need a new filter for my brain.K-N,OEM,

I'm more frustrated than a three legged dog trying to bury a turd on a frozen lake!!!

Greaser · Mar 8, 2003

quote:

Originally posted by Bootlegger:
After reading all this I need a new filter for my brain.K-N,OEM,

I'm more frustrated than a three legged dog trying to bury a turd on a frozen lake!!!

Americanflag · Mar 8, 2003

Get used to it, it only gets worse.

Many smart auto enthusiasts use the K&N. I am pretty sure it is the best filter made.

DABEAR95 · Mar 10, 2003

I use a K&N in my performance vehicle (camaro) and a paper filter in my point A to B car...

Jason

Americanflag · Mar 10, 2003

I want to put a filterwrap around my K&N. I emailed them, I hope they make one for my filter.

I am pretty sure the K&N is a fine filter. I am starting to think the problems come when people service them, i.e. overoiling, tearing up the filter, etc. I think I will run mine to 30-40 thousand miles, without servicing it, then maybe change to another filter.

Greaser · Mar 10, 2003

quote:

Originally posted by Americanflag:
I want to put a filterwrap around my K&N. I emailed them, I hope they make one for my filter.

I am pretty sure the K&N is a fine filter. I am starting to think the problems come when people service them, i.e. overoiling, tearing up the filter, etc. I think I will run mine to 30-40 thousand miles, without servicing it, then maybe change to another filter.

I know it blows when you spend money on a product then second guess yourself...I took mine out and put them on the shelf

...they might work allright in some applications...and stink in others...not worth the worry as far as I'm concerned and went back to a quality paper filter...to each his own.

Americanflag · Mar 11, 2003

Yeah, I may take mine off as well. Really, I should do a oil analysis for Si, that would settle the matter once and for all.

I mentioned that Mobil 1 told me the K&N is the best filter made BTW. I wish K&N would do more research, or if necessary, reduce the air flow a little and increase filtration.

They said they don't make a filter wrap for my model filter.

SAE reports on air cleaner service life and engine wear

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