K&N Style Air Filter

Brucebotti

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Has anyone switched to a K&N (or similar) style air filter? I was looking at one for my Kawasaki FR691V. They are about twice the price of the OEM filter, but will last forever. I have used them on several autos, and also on my Sears SS12, and then on my just retired Craftsman mower. I have never experienced any issues with them in the past 30-40 years. My only concern is whether it will affect the warrantee. I will probably hold off until the warrantee is up.
Thanks,
Bruce
 

Brucebotti

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I'm surprised....nobody uses a K&N (or similar) air filter?
Thanks,
Bruce
 

Carscw

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I run them on all my mowers.

(( racing is the only sport that you need two balls ))
 

Brucebotti

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I run them on all my mowers.

(( racing is the only sport that you need two balls ))
Carscw,
With the price of air filters and the abuse they take, it seems logical, as long as I can find one that fits. On my old Sears SS12 and my Craftsman GT, I found ones from harley's that fit. They cost me $30-35 each, compared to a $12-15 paper filter. The only thing I am concerned about is the warrantee, althogh this shouldn't be an issue.
Thanks,
Bruce
 

tuit

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I see those K&N type filters all the time, I turn wrenches at a Ford dealership. All those type filters are good for is keeping things like bugs and rocks out of intake/carburetor. I regularly see diesel turbo chargers which pulls in filtered air have 1/8 inch deep oil soaked dirt inside the turbo charger compressor housing inlet and the fins inside worn down smooth from the dirt sand blasting them off.
If there is dirt past the air filter, Its called a dusted engine. Warranty will not cover/pay for that repair since it was not the fault of their part. That's some of the problems that you get into by trying to save money by not using manufactures parts. People don't realize that also applies to their cars.
Good rule of thumb is if you can see day light thru the filter, dirt/dust will pass thru it.
 
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exotion

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I see those K&N type filters all the time, I turn wrenches at a Ford dealership. All those type filters are good for is keeping things like bugs and rocks out of intake/carburetor. I regularly see diesel turbo chargers which pulls in filtered air have 1/8 inch deep oil soaked dirt inside the turbo charger compressor housing inlet and the fins inside worn down smooth from the dirt sand blasting them off. Good rule of thumb is if you can see day light thru the filter, dirt/dust will pass thru it.
Its just so much better to use the oem paper filters in cars they are cheap and don't even have to be changed that often... 10 to 25 k miles. I knew someone who said he like the k&n because it keeps water out betterand drys I just told him if you have that much water near your intake you have bigger problems lol
 

Carscw

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The problem is not the K&N filter on a car a truck or a mower the problem is the owner thinks you just put the filter on and forget about it.
You need to keep it washed and oiled. The small dust and or dirt gets trapped by the oil.
It's like anything else it's only has good has the person using it.

If K&N filters were not good to use then why would the shop that built my $30.000 engine tell me to use one

I also use K&N oil filters The only oil filter a machine shop says not to use is a Fram

(( cowboy up and get over it ))
 

exotion

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The problem is not the K&N filter on a car a truck or a mower the problem is the owner thinks you just put the filter on and forget about it.
You need to keep it washed and oiled. The small dust and or dirt gets trapped by the oil.
It's like anything else it's only has good has the person using it.

If K&N filters were not good to use then why would the shop that built my $30.000 engine tell me to use one

I also use K&N oil filters The only oil filter a machine shop says not to use is a Fram

(( cowboy up and get over it ))
Lol fram.... I've heard sooooooo many storys about them I vowed nothing with the label fram is ever going to touch anything I own.
 

Brucebotti

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The problem is not the K&N filter on a car a truck or a mower the problem is the owner thinks you just put the filter on and forget about it.
You need to keep it washed and oiled. The small dust and or dirt gets trapped by the oil.
It's like anything else it's only has good has the person using it.

If K&N filters were not good to use then why would the shop that built my $30.000 engine tell me to use one

I also use K&N oil filters The only oil filter a machine shop says not to use is a Fram

(( cowboy up and get over it ))
I agree. The only problems that I have ever heard were due to operator / user error. I have had very good luck with them.
Bruce
 

afoulk

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Some work, some don't. I've seen UOA's ( Used Oil Analysis) results for cars that ran K&N filters and some have had much higher levels of silicon (dirt) in their oil samples, while others have run K&N's in their car, and the levels were the same as with the factory paper filter. I just choose not to even risk it and run the factory filters, even if they are a few bucks more than the aftermarket replacements such as Fram or Purolator, I find most times they fit better anyways. I do the same with my lawn mowers.
 

motoman

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There is a vast literature on the benefits and liabilities of the K & N type vs paper filters. IMO and what I have seen a high revving engine (NOT tractors) there "may" be a HP or 2 through the foam, but over and over they have been shown NOT to screen fine particulate matter (dirt) as well as paper. If you mow in dusty conditions (worst here when I hit a mole mound) paper is the only choice. Those with the foam-oiled pre filter will note it is used as the first barrier only. The most definitive testing I have seen showed that good ole AC made the best paper filter RIP.:2cents:
 

djdicetn

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There is a vast literature on the benefits and liabilities of the K & N type vs paper filters. IMO and what I have seen a high revving engine (NOT tractors) there "may" be a HP or 2 through the foam, but over and over they have been shown NOT to screen fine particulate matter (dirt) as well as paper. If you mow in dusty conditions (worst here when I hit a mole mound) paper is the only choice. Those with the foam-oiled pre filter will note it is used as the first barrier only. The most definitive testing I have seen showed that good ole AC made the best paper filter RIP.:2cents:
I switched to K & N filters for my 1995 Chevy Silverado and 2001 Lincoln LS and I keep them cleaned and re-oiled regularly(every 50K miles, not the recommended 100k-150k that K & N states). When I clean/re-oil them I am still "not able to see daylight through them" so I think they may be OK for those applications. But I agree about being weary of using K & N filters in very dusty environments(even regular vehicles if you like in Kansas or if you drive off-road a lot) and I would be reluctant to use that type of filter in a lawn equipment application. Yeah...you're spot on about the AC/DELCO air filters(used them fo many years on my Chevy truck)....but GM has gone cheapo on the newer ones(as well as the AC/DELCO oil filters where they make all application filters "smaller than the OEM filter" to save a couple of bucks in the extra metal, etc. used to manufacture the OEM's. Sad, isn't it:0(
 

The-Dude

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I put one on my Husqvarna lawn tractor, it works great.

You can look for your specific Lawn Tractor here.
You can use their search by dimension feature to find one that fits your tractor if yours is not directly listed.

I suggest using the air filter wrap over the filter. Help stop large debris from getting into the filter.
 
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turbofiat124

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I don't know if this is any indication or not but I've been running one of those Unifilter foam filters on my 21hp B&S engine for a couple of years and have never seen any dirt on the neck after the filter. I don't know if that's any indication that it's doing it's job. The engine oil doesn't seem to get any dirtier than when using the paper filter nor is the engine using any more oil than it did before. I guess the real test would be to do a yearly compression test.

When the filter is dirty, I just stick it my parts washer of kerosene and the dirt falls right off. Afterwards I had been dunking it in a jar of 50/50 kerosene and ATF then letting it drip off over night then sticking it back on the mower the next day but I've been using that PJ1 foam filter oil here lately.

Here some pics from a thread I posted yesterday:

https://www.lawnmowerforum.com/showthread.php/57180-K-amp-N-filter-for-B-amp-S-engines

The mower with the K&N knock-off, I made a sock out of that foam air cleaner material which adds a second layer of filtration.

This UNIfilter on my 21HP B&S is not much different than the foam filters used in lawnmowers before they started using paper filters. If these foam filters are so bad for engines as people claim, then how come B&S used them for ages? You could clean and reuse those things over and over until the foam started to break down and turn to powder.

My guess is people these days just don't like to get their hands dirtier anymore than they have to. It's more convenient to pay $15 to $20 for a paper filter 2 or 3 times a year than it is to wash their hands.

The procedure for cleaning the old foam filters was to wash it in hot soapy water (or kerosene), let it dry, then pour motor oil onto it and squeeze out the excess.

Just like they stop putting back-up recoil starters on riding mowers. People would rather just push a button. I guess eventually I'll get to the point to where I can't start a lawnmower due to age by pulling on it and will have to depend on an electric starter.
 
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