Tapping dust out of air filter

MParr

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txnowman, I don't know the serial #. To be honest its too darn hot to walk out there and look it up :). It is 100 here. If it helps any, the mower is a Toro MX5060, model 74641, with a Kawasaki 23hp engine. I "think" the mower came with just the paper filter and not a foam sleeve over that filter. But thats 12 years ago and I've changed filters 2 or 3 times. I don't recall but it may be another brand filter thats on there now. I really don't know. I put that foam sleeve over it that came with a prior filter. I figure as thin as that foam sleeve is its not going to hurt in any way.
FWIW: Change the paper filler and foam pre-filter once a year or every 100 hours, whichever comes first.
You can blow out the paper filter or tap the dust out whenever you feel like it. For the foam pre-filter, wash and dry every 25 hours and lightly coat with a spray foam filter oil.Vacuum and wipe the filter housing with a damp cloth when you pull the filters.
 

slomo

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Don't forget a little grease on the sealing edge of the paper filter. Messy but traps dirt and grit.
 

bertsmobile1

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Good job. Critics of me being thrifty would probably be right. I do have a foam covering over the filter. It broke; I'll get another today. Even with the foam filter (which I've not coated with anything) the paper filter gets a ton of dust in it. Maybe thats something I shouldn't worry about and just take it off every other mowing and tap it out instead of doing it twice a season like I've been doing. I read somewhere once, I don't remember where, that I should not use that foam filter. Why, I don't know. But I use it anyway. Whatever, after a couple of those real bad dusty days I know tapping it releases tons of dust, and the foam filter is coated. I'll look around and see if I can find modifications to my model engine that can be bought or made.
NO
Like tour mother told you in the bath tub
Leave it alone or it will fall off .
The problem with the Kawasaki air filters is the elbow getting it to seal properly either end is quite difficult and every one a customer has replaced the elbows were over tight causing a leak, usually both ends .
So don't touch it till you see signs of rich running then replace it
Worth putting a light bead of silicon sealant on the male ends before inserting them then lightly tighten and don't touch it for as long as possible
Two customers have needed new rings in their Time Cutters due to dust being sucked in around the elbow
If it clogs to the point of running rich then you know it is doing it's job
If the engine always runs clean then the filter does not need to be replaced .
My wholesaler puts together a conversion kit that has been certified by Kawasaki to convert FS & FR to FX filtering and does not affect warranty

Kit for small engines that use a shorter single element filter
Kit for larger engines that use the 2 element filter
Note that these are all genuine Kawasaki parts
When I fit them I mount the filter canister on the right side ROPS vertical so it is well above the engine & does not obstruct access to it
Mounting on the blower housing makes pulling the housing off a bit tedious
The kits above both have steel blower housings with them which doubles the price and fitting to the ROPS means the original plastic housing can remain and I just use some convoluted tube to go between the filter & the carb.
One has been on for 5 years now without a problem, in fact it is still running the original filters
Pulling air from above the dust zone makes a massive difference
As I previously mentioned Victa fitted them to their push mowers and I have some of them that are still running the original air filters some 20 years latter.
Most that I replace are choked with spider webs or mud wasp nests , not mowing dust & grass clippings
Compare them to the side panel filters fitted to modern Honda & B & S engines which rarely last a single season, remembering we get 40+ C days and mow around 40 times a year down here .
On the mowers with air intake snorkels the story is the same
After 5 years there is a small oval of dust on the side panel filters and no visible dust on the top mount Honda filters .
 

txmowman

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It is so appalling reading the advice of so called 'engine experts' on this forum. Why does the owners manual say to "tap out" the filter? That is because it is paper and any compressed air will damage it. Can you blow through a piece of paper? Only if it already has micro holes in it, like the media of any air filter. How low of air pressure will not change the size of these tiny holes? My guess is probably not a lot.
If it needs to be blown out, it probably needs replacing. The manual says to not oil the pre-filter. Why? Because oil attracts dirt. And, there is no need to order an illegal aftermarket air filter system, if someone would have ordered the correct engine for the job to begin with.
Kawasaki offers a 3 year warranty on all engines against manufacturing defects. Dirt ingestion is not a manufacturing defect.
 

7394

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Just my .02, the foam filter will only stop twigs & leaves etc.. Oiled, it will stop much more, but will require cleaning much more often.

What I have tested is a womans nylon stocking, stretched over the FS air filter. ( 1 layer) that is so fine that it helps..

But best is the 2 stage Donaldson set up, like the FX Kaws run..
 

txmowman

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Just my .02, the foam filter will only stop twigs & leaves etc.. Oiled, it will stop much more, but will require cleaning much more often.

What I have tested is a womans nylon stocking, stretched over the FS air filter. ( 1 layer) that is so fine that it helps..

But best is the 2 stage Donaldson set up, like the FX Kaws run..
I could live with that 7394, as long as the oil is minimal, as to not wet the paper element. Seriously, if you live in the south, where there is more fine dirt than grass, spend the extra $ and get an FX engine.
The FR filter is fine for those who are maintenance minded, but there is not near the filtering capability of the FX.
If the rubber tube is installed correctly and the clamps are TIGHT!, you will not have issues. You would have to try damn hard to over torque a clamp. The air's pass of least resistance is through the filter media. When it can't filter any longer, the engine will get air from wherever it can.
 

bertsmobile1

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It is so appalling reading the advice of so called 'engine experts' on this forum. Why does the owners manual say to "tap out" the filter? That is because it is paper and any compressed air will damage it. Can you blow through a piece of paper? Only if it already has micro holes in it, like the media of any air filter. How low of air pressure will not change the size of these tiny holes? My guess is probably not a lot.
If it needs to be blown out, it probably needs replacing. The manual says to not oil the pre-filter. Why? Because oil attracts dirt. And, there is no need to order an illegal aftermarket air filter system, if someone would have ordered the correct engine for the job to begin with.
Kawasaki offers a 3 year warranty on all engines against manufacturing defects. Dirt ingestion is not a manufacturing defect.
Yes I agree
However in a civilized society people can have different opinions and while I try to point out things that are bad or incorrect it is not my job to change peoples minds
In many cases a mower engine will run fine for a very long time with no filter at all
Motorcycles rarely had a filter on the carb till almost WWII and even then a lot of sports bikes ( and cars) had nothing more than a coarse screen to stop sticks & stones
Mower engines do so few hours that abrasion from dust ingression to the point of engine failure is highly unlikely to happen before the mower parts themselves fail .All of the ring failures have been on ZTR's with baggers that exude a massive amount of very fine dust very close to the air intake and when bagging people tend to mow slower so a lot of that dust gets sucked into the blower housing then blasted into the filter chamber

Filters should not be blown out with compressed air unless that air has been eletrostatically filtered before being compressed
The filter shop I use that "dry cleans" filters used on earth moving equipment has $ 20,000 worth of gear that microscopically cleans the air down to 0.1µ and then pulse blasts the air filters from the inside out .
The maximum number of times they will do this is 11 and they test them prior to sending them back with smoke ≈ 2µ particle size .
OTOH this gear can ave filter that go better than $ 100 a pop and can clog up in less than 8 hours of use .

I fit FS engines because they are over $ 1000 cheaper than FX's which are over kill for domestic customers
RGS supply the upgrade filter kits for about 1/2 the price difference and without the steel blower housing that comes down to a 1/4 .
They are not "ILLEGAL" they are authorised by kawasaki and come with a warranty continuation certificate , if fitted by a recognised technician.
As I have tried to emphasise the biggest problem is in the fitting.
Clamping onto a plastic tube is not a good idea as you can easily deform the tube and create an air leak .

The purpose of the foam is not to filter dust bit to hold back grass clippings that block off large sections of the paper surface so no need to oil them
Foam only filters do need to be oiled but they are very thick and work by causing the air to follow a turbulent path so the dust will hit the oiled surface thus stick to it .
This does not happen very much with prefilters because they are way too thin to do any effective filtering , they are a screen and are only foam because foam is cheaper than wire mesh

Pople see stuff on the web that dose not apply to them or their situation then blindly apply it where it does not belong because they have not thought it through properly to start with.
 

txmowman

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The difference in retail price between and FR and an FX "engine" is $200-300. Maybe on a mower there is $1k difference? If that is the case let me clarify. For those who do not do proper maintenance and fail their FR engine, replace it with an FX.

It is ILLEGAL, as in a violation of EPA regulations to retrofit an FR with the FX canister filter system.

Lastly, I will sell you as many engines as you like that you can run without an air filter.
 

bertsmobile1

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The difference in retail price between and FR and an FX "engine" is $200-300. Maybe on a mower there is $1k difference? If that is the case let me clarify. For those who do not do proper maintenance and fail their FR engine, replace it with an FX.

It is ILLEGAL, as in a violation of EPA regulations to retrofit an FR with the FX canister filter system.

Lastly, I will sell you as many engines as you like that you can run without an air filter.
I can not see why fitting an air filter that is available as an add on option to the mower when new would be illegal
But then I can never see any sense in most of what governments do particularly EPA's yours or ours
I can not reproduce & post my Feb 2022 wholesale kawasaki price if I want to keep selling them but the difference in price I pay from my distributor for the FX 691v to the FR 691v is $970 ( Aus)
Add my 30% mark up +10% GST on top of that and it comes out at $ 1387 to the customer which used to be more than $ 1000 when I went to school
I am expecting an update to that price list as that wholesaler just added 9.5% across the board to all prices as of July 1 which is the beginning of our financial year .
I can fit the double element Donaldson for just under $ 300 or the single element Enginaire for just under $ 200 and both of those prices include the air flow meters to tell you when to change the filter so you don't damage the soft sealing faces checking to see if a good filter needs replacing .

I presume you are a technician of some sort so I would ask how many old Sprint engines come in with next to nothing of the foam filter left in the housings
And how many of the leave working fine with an oil change & a new filter fitted ?
Now for an all alloy bore things would be different.
FWIW Kawasaki use a soft bore and hard rings so the cross hatching wears off quickly after which the rings can no longer maintain a good seal to the bore .
 
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txmowman

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I've seen well maintained Kawasaki engines used on oil rigs, with several thousand hours, where the bore looks as if it was just honed. Rings do not wear a cylinder if the engine is properly maintained.
Anybody that knows this industry, knows John Deere is the king. How is it that JD would primarily use Kawasaki engines in their commercial line for more than 30 years, if they were not a commercial grade engine?
ALL lawn mower engines need need great credit. Think about this people, A lawn mower engine runs at 3,600 rpm, sometimes for 8 hours a day. What would it take to get your truck to do the same? Probably doing north of 100 mph to reach 3600 rpm? Doing it in second gear? Would you do this? Would you ever think to stop and check the oil or anything? The problem today is that we've been conditioned by mostly the big box companies that we can use and abuse something. When it fails, we just return it. Well, a lot of you shop owners and sales organizations are not big box stores. You don't have the room or the clout to do business this way. Now, go out and give your mowers some love.
 
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