Air Filter - Engine

Topic: Air Filter - Engine (Read 3048 times) previous topic - next topic

Re: Air Filter - Engine

Reply #25 – August 14, 2010, 08:40:28 pm

Quote from: fjm502 – August 11, 2010, 08:10:15 pm

I have had the filter minder show a marked increase in vacum after driving in a heavy rain but went back to normal next day. Believe I read this was ok and did not warrant a filter change. Correct me if I am wrong.

I think that would be correct to ignore any readings obtained after driving in heavy rain and to recheck later in dry weather. A wet paper air filter will have more restriction than a dry one. Personal experience with a gasoline engine powered pressure washer proved that to me. The paper air cleaner became wet because of a water spray leak from the supply hose; the engine ran rich as though the choke was closed with very little power.

My FT has a water separator before the air filter and earlier models may have them too. However in a heavy rain the paper filter may become damp. Other owners have reported leaves and trash on the screen above the water separator.

Air filter change

Reply #26 – June 26, 2011, 03:55:19 pm

I have described my experience changing the air filter with photos in the attachment in hopes it may help someone.

Re: Air filter change

Reply #27 – June 26, 2011, 04:13:17 pm

Dick, I loved your coverage of the air filter replacement. I feel people should not blindly trust the restriction gauge, like your info, I have never seen my gauge show any indication of restriction even when I remove the cartridge, it looks nearly as bad as your filter, when I do the light test, can see clearly how restricted it is with very little light showing through.
Your pix and wording should make it perfectly clear.
Thanks

Re: Air filter change

Reply #28 – June 26, 2011, 04:58:49 pm

Good job, Dick,

Too bad the filter is such a weird shape. It sure make replacing it a real challenge. BTDT.

Re: Air filter change

Reply #29 – June 26, 2011, 06:56:19 pm

Dick,
I really enjoyed your description and pictures of changing your air filter. However, it generated a host of questions: In my '92 U-280, 300 hp Cummins setup, the filter orientation is exactly opposite, in that

1) the small end is inserted first and fits snuggly at the very back of the canister

2) air is drawn directly through the outside grill into the large, open end of the filter, into the core and through the outer circumference of the filter.

3) thus, the inside of the filter gets dirty, not the outside

4) there is no place, at least that I can see, to use the large diameter foam rubber gasket that is supplied with the filter. The very first time I replaced the air filter, I was careful to take note of all components and gaskets. There was no foam gasket around the circumference of the large opening of the filter. Thus, I was perplexed at not knowing where to put this large one until I saw your pictures

5) In your picture number 6, a tiny (~1/8") hole is shown clearly in the small end of the filter. Thus with my filter's orientation, that hole allows dirty, unfiltered air to bypass the filter media and directly enter the clean side (outside of the filter) of the canister and the intake to the engine. Therefore, I have been placing a small patch of duct tape over the hole from the inside of the filter. Am I interfering with the air dynamics by blocking that hole? I just couldn't see allowing dirty air (albeit a small amount) to enter the engine.

I would appreciate hearing from any of you about this and in particular, from fellow Grandvilla owners who have the same air filter arrangement.

I intended to post pictures, but the coach is currently at MOT, where they are replacing our 6 years (to the day) old Dometic with a new one.

Re: Air Filter - Engine

Reply #30 – June 26, 2011, 07:14:33 pm

Don, I do not know your filter setup, BUT on my 01 320, like the 03 320, on the small end there is a hole in the center but there is also a rubber gasket around the small end of filter, this is to seal off the outside air. The reason for the small hole is so the filter minder can get a sniff of the vacuum / restriction.

Re: Air Filter - Engine

Reply #31 – June 26, 2011, 08:07:27 pm

Don, I wish I had a photo of the large end of that filter. But I'm 99.9% sure that it also has a seal glued to it. So the seal at the large end seals around the opening at the back of the canister, which is the engine air intake, and the one on the small end seals on the cover. Unfiltered air comes in through the large hose on the side of the canister and because of the two end seals goes through the outside of the filter and out to the motor. I agree with Dave that small hole is for the filter minder.
Some photos of your system would help.
Some time ago a mechanic explained an oil saturated K & N filter to me and I think ours work the same way. The filter media will get plugged first where the dirty air hits it. But then that air starts to go through a clean part of the filter further down or around. This continues. So the filter media really has a large surface area and probably explains why the filter minder shows no restriction when we see all that crud. Somewhere on the other side and way down at the other end, it's clean enough. Well that's my story anyway ...

Re: Air Filter - Engine

Reply #32 – June 26, 2011, 09:07:48 pm

Dick,
You are correct: the large end of the filter has a foam seal/gasket glued to it, and in your system the large end seals against the back of the canister. However, in my system the foam gasket on the large opening seals against an open bracket that centers the cartridge in the canister and seals off the outer canister compartment (space around outside of filter). Outside air flows over the bracket and into the center of the filter. In our system there is no "large hose"; air comes directly from the outside, around a baffle and into the large opening of the filter. Interesting differences between the Unicoaches and Unihomes.

So Dave thinks the tiny opening is for the filter minder? That would mean that my sealing it off prevents the minder from doing its job, but also stops contamination into the engine.

Tomorrow when I pick up my coach, I'll take some pics and send them on.

I really appreciate the great pics when you work on your coach.

Re: Air Filter - Engine

Reply #33 – June 26, 2011, 09:10:14 pm

Dick S,

Thanks for all the pictures of a really dirty air filter. I have the same air cleaner and filter, but FT installed it differently. It sits sideways behind the hydraulic pump and just clears the engine door. The air enters the end and goes out the side opening rather than the other way around as on yours. Air passes through the large end of the filter so that dirt is trapped inside the filter. Doubt if the dirt cares about which way is better. It's a little harder to get to the hydraulic pump belt, but maybe a little easier to remove the oil filter with it mounted across. The suction line for the gage is mounted on the side rather than the end cap. If your gage didn't indicate a dirty filter, it's rather worthless.

Re: Air Filter - Engine

Reply #34 – June 27, 2011, 12:26:08 am

You have all talked about the exact reason I designed and installed the Rear Air Deflector I made on my coach. I said at the time that last Nov when at FOT I asked the mechanic what the filters usually look like when they do the servicing and he said "real bad". I have had this on the coach for a year now and last trip was 12,000 miles thru' all kinds of weather and dusty roads in Mexico. I took a look at the filter last week and it is almost still like new with no crap etc inside housing (unlike before doing it). I am very pleased with what it is doing and can rest easy knowing the likely hood of any damage to turbo etc is removed. I know the reasons for not taking a look at the filter due to the chance of particulate loosening and going into engine, but having done this for many years in the construction field on large deisels for cranes and never a problem I do take care not to knock it or? My care on my unit is 100% better than many mechanics who are paid to service our units, and I did work for a few years in the building of both Jet and helicopter engines in England. A little bit tighter specs than Deisels.

Re: Air Filter - Engine

Reply #35 – June 27, 2011, 12:43:12 am

Quote from: Dick S – June 26, 2011, 08:07:27 pm

Don, I wish I had a photo of the large end of that filter. But I'm 99.9% sure that it also has a seal glued to it.

Just checked the spare filter here at the house, there is a seal glued on both ends and a loose one for the cap.

Re: Air Filter - Engine

Reply #36 – June 28, 2011, 06:24:44 pm

Quote from: Barry Beam – July 22, 2010, 12:09:16 pm

Since I have never seen my filter minder gauge move, I thought it might not be working.
So I pulled off the small diameter rubber hose at air cleaner and very light sucked by mouth on the hose
and low and behold the filter minder gauge moved right up,so it works,
it is just my air cleaner does not get dirty enough to cause a vacuum inside the filter.
I have read in a motorcade article
"The fact is most air filters are changed too frequently".
So I sent some photos to James Triana asking if this filter was considered dirty and replacing.

The recommendation from the engine manufacture would be to replace the filter if removed.
If I were working on the unit and saw a filter like this I would replace it.
At the filter canister make sure the brass elbow is not stopped up or plugged.
Make sure filter is not installed backwards, as I have seen this happen before.
If memory serves me correctly I think the minder runs around 10 – 12 inches of vacuum at normal operation and new filter.

So this filter looks dirty to me but the minder has a mind of its own.
Whats a person to do

More info on the Motorcade Article:
beamalarm.com/Documents/know_your_air_cleaner.htm

I posted this article on iRV2.com/Monaco

Engine O&M Guides do not list air filter service interval information because that is not something that is predictable like lube oil, fuel or coolant filter service intervals. Air filters will accumulate dust at varying rates due to ambient conditions depending on terrain, location, traffic, and weather. Because of these varying and complex interaction conditions, air filter service you should be doing is NOT inspecting the filter element to SEE if it is plugged. The most reliable and safe method for determining air filter condition and remaining life is to use a restriction gauge such as the Filter Minder(tm) by Engineered Products of Waterloo, Iowa. This product is now the most commonly used indicator in the engine business, LD, MD, and HD diesel (some gasoline).

How does a Filter Minder Air Filter Service Indicator work?

Restriction indicators are able to measure the small pressure differences between the ambient air pressure and the air pressure on the clean side of the air filter. Most engine manufacturers list the upper limit of air filter life as being 25 inches water, about 1 PSI difference in air pressure. Engine ECM controls measure manifold absolute pressure and adjust fuel rates accordingly. It would appear that most MH operations do not achieve sufficient run time and miles to bring on air filter plugging. If you check your restriction indicator, you may see little movement and conclude that it does not work. This is a common but unfortunate outcome even for large on-highway truck fleet operators who commonly put on 125,000 plus miles per year. For them, with their miles, they frequently change the air filter yearly, whether it is needed or not. For them, that works as they generally keep their units for 4 -5 years then trade them off.

For the MH operator a yearly air filter change is much less desirable as the miles involved are few. Air filters will pass dust when first installed. Usually, it will be during the first 25 hours of normal operation. New air filters are usually 99.3% efficient but after the initial 25 hours the efficiency goes up to 99.8%+ and remains for the duration until the 25 inch restriction limit is achieved. Fewer changes will equate to less dust ingested due to filter service. Any ingested dust is cumulative. Eventually, with enough changes the accumulated dust will reach 4 - 5 ounces, enough to cause cylinder bore and ring wear on a midrange size engine like a Cummins C, ISC, ISL, Caterpillar C9, C12 and comparable engines from International and Detroit.

While it is undesirable to get an air filter wet, the effects are usually short lived. Wetting the air filter will cause the indicator to rise, sometimes to the point of achieving the maximum restriction. It is an easy matter to check the restriction and reset it. Do not change the air filter because of that instance. If it rises to a high restriction level quickly again. Service the element at that time and reset the indicator.

What I am recommending you do for a PM interval for the air cleaner system is to determine that restriction indicator is functioning correctly. If it fails to lock up showing maxium achieved restriction the indicator does you no good. Then you may be forced to change the air filter if you have such doubts.

To test a restriction such as the Filter Minder(tm), operate the engine a low idle speed. Cover the air inlet such that you are inducing an artificial restriction simulating plugging conditions on the air filter. As restriction rises, you should see the indicator rise to some level and hold in that position when you remove the restriction. Shut the engine off. Push the yellow rubber button on the bottom of the Filter Minder(tm). It should drop down to the lowest level. If it does not, the sensing line or small brass fitting is plugged. The small brass fitting on this device has a porous bronze filter. Sometimes they become plugged with dust. There is also a very small orifice hole in the bronze filter fitting. It has been known to plug. If the gauge does not reset, remove it and the brass fitting to clean the fittings. Blow them out with compressed air and use of some solvent or even water. When you re-install the gauge, be careful not to see how strong you are. The Filter Miner(tm) now is made with a straight thread and o-ring seal. It can be hand tightened easily. If you have the earlier style, it has tapered pipe thread. It was easily possible to over-tighten that gauge and crack the housing.

What if the gauge does not lock up during the restriction test? In that instance the gauge is faulty. Replace it.

For some there may be the original restriction gauge from Donaldson. It has a red flag indicator with no means of showing advancing restriction. I would recommend replacing that gauge with the one listed above.

That is all there is to PM interval based air filter maintenance. You should periodically check the rubber boots and band clamps. The rubber boots and elbows on the clean side of the air filter must remain pliable for the band clamps to be able to seal. Due to heat and time, the rubber will take what is called a 'compression set' and become hard. Removal of those boots and connectors and re-installing may not result in the same level of air tight seal that you need to prevent dust ingestion. This is especially important if your air cleaner is a Far Ecolite or any replaceable housing air filter. Tightening the clamp may make the clamp tight but the boot hose does not clamp onto the air housing.
__________________
Gary Spires (W9GAS), Field Service Engineer
Coolants, Cooling Systems, Filtration, Diesel Engines
https://picasaweb.google.com/garyspires45

Re: Air Filter - Engine

Reply #37 – June 29, 2011, 12:01:00 am

I managed to take a few pictures of the arrangement of the air filter canister in a U-280 Grandvilla. Hopefully it will add to the description I made a few days ago. I added a 1/4" hardware cloth cover over the canister intake, as I have in the past, retrieved full 8 1/2"X11" sheets of paper as well as large oak leaves from the inside of the filter.

The tear-drop shaped fiberglass shield rests on top of the bracket , so that there is about a 3" deep clearance between the fiberglass cover and the filter intake. A profile picture illustrates the depth. The duct tape on the edge of the hardware cloth was to blunt the sharp edges.

I am including a pic of the extra foam gasket, to show that there is no groove in which it can fit in this setup.

The filter minder tube inserts very close (within 4") to the actual engine intake near the end of the canister.

Is this arrangement the tiny hole at the end of the filter is sealed off from the outside of the filter by the smaller foam gasket at the end of the filter, so I don't see how it could influence the filter minder.

What appears to be a large hole at the back of the filter is just a circle of sun light, though it is deceiving.

Hope this clarifies things for a '92 U-280.

Re: Air filter change

Reply #38 – June 30, 2011, 11:26:17 am

Quote from: Dave M – June 26, 2011, 04:13:17 pm

Dick, I loved your coverage of the air filter replacement. I feel people should not blindly trust the restriction gauge, like your info, I have never seen my gauge show any indication of restriction even when I remove the cartridge, it looks nearly as bad as your filter, when I do the light test, can see clearly how restricted it is with very little light showing through.
Your pix and wording should make it perfectly clear.
Thanks

The problem that MHers have is that you do not run the coach long enough (miles) to see the air filter collect significant dust. So, you do not believe the device works. They work and work very well. Your air filter is capable of holding a few thousand grams of dust if run to the 25" water restriction (red band on the Filter Minder). Most on-highway 18w trucks average 125,000 miles yearly. Their restriction gauges rarely indicate higher than 15". In field return testing of air filters from our truck customers we have found that at the 125K - 150K miles, the restriction is not close to being maxed out. Our recommendation on air filters is to run to near maximum restriction. See my article I posted above. You can sure judge an air filter by its looks but like judging people, it is what you cannot see that matters. They 'look' dirty. Means nothing. But as a service engineer for a filter company I think I can speak on behalf of all filter company service guys.....thanks for changing your air filter too frequently. It helps our company a lot to have the increased sales.

I have told countless truck customers that they are spending too much money on our air filters by changing needlessly. Sales guys do not like that but it is solid technical advice.

Re: Air Filter - Engine

Reply #39 – June 30, 2011, 11:54:46 am

Gary, I thank you for your view on having a dirty filter,

My thoughts: if the filter companies are selling filters that need to be pre clogged to make them effective, that maybe they would offer such filters instead of selling non effective filters until they collect half a pound of dirt.

Maybe the big problem with the K&N filters is simply, they take too long to catch enough dirt to make them effective ?

For me, when I put a bright light inside a filter and see very little/no visable light shining thru to the outside in a shaded area, I feel just maybe it needs replaced, I never thought it was just approching its prime of life.

Re: Air Filter - Engine

Reply #40 – June 30, 2011, 12:12:48 pm

Quote from: Jerry Whiteaker – June 26, 2011, 09:10:14 pm

Dick S,

Thanks for all the pictures of a really dirty air filter. I have the same air cleaner and filter, but FT installed it differently. It sits sideways behind the hydraulic pump and just clears the engine door. The air enters the end and goes out the side opening rather than the other way around as on yours. Air passes through the large end of the filter so that dirt is trapped inside the filter. Doubt if the dirt cares about which way is better. It's a little harder to get to the hydraulic pump belt, but maybe a little easier to remove the oil filter with it mounted across. The suction line for the gauge is mounted on the side rather than the end cap. If your gauge didn't indicate a dirty filter, it's rather worthless.

Foretravel used the Donaldson EBA air cleaner housings. That housing came in two flavors, KP I an KP II. The KP I housing has the dirty air inlet on the end opposite the cover. The KP II has the air inlet as an opening in the service cover. The air filter element is the same in both housings but the large open end is always inserted such that it faces the incoming dirty air. Both housing types have a cover gasket that may not appear to "fall into place". It does not. It is stretched over the housing diameter under each of the four studs. Failure to install this gasket provides an excellent dust entry point and subsequent engine destruction from inhaling dusty air.

While air may not care which way it goes through the element, the service life of the element is less with an inside out flow design on all air cleaners. This is due to the inner diameter pleats being closer to touching thus restricting air flow more and packing with dust faster. With an Outside-In element, the pleats are more open and spread apart thus more air and more dust capacity.

Re: Air Filter - Engine

Reply #41 – June 30, 2011, 12:21:50 pm

Quote from: Dave M – June 30, 2011, 11:54:46 am

Gary, I thank you for your view on having a dirty filter,

My thoughts: if the filter companies are selling filters that need to be pre clogged to make them effective, that maybe they would offer such filters instead of selling non effective filters until they collect half a pound of dirt.

Maybe the big problem with the K&N filters is simply, they take too long to catch enough dirt to make them effective ?

For me, when I put a bright light inside a filter and see very little/no visable light shining thru to the outside in a shaded area, I feel just maybe it needs replaced, I never thought it was just approching its prime of life.

Dave,

We could design an air filter that has much higher initial restriction. That is a no-brainer. But you would have very little life from such a product. Air filter paper has a pore range of 0.5 micron to 5 micron for the largest population of pores. A micron is 39 millions of an inch. A lot of dust, especially in the Southwest is in the sub-micron range. This is an issue for some customers as air filters still pass more of that size dust especially when the air filter is changed too frequently (before 22 inches water, 25 inches maximum).

The K&N type air filters can never catch significant dust due to their pore distribution being much larger than a paper element. Their claim is they can pass more air for those engines that have had the ECM jacked up to produce twice the HP the OEM designed the engine for. That type does do as advertised....increase air flow. They do not brag about their ability to remove dust unless you think their 96% removal is good. We consider a paper element in your application to be failed if it only achieve 99.6% dust removal (light duty app).

Re: Air Filter - Engine

Reply #42 – June 30, 2011, 01:13:16 pm

Gary, the local industrial supply house I use to buy filters told me "here in the NW where we have so much rain and moisture in the air, I recommend changing these air filters every year". He feels the moisture affects the paper.
What say you?

Re: Air Filter - Engine

Reply #43 – June 30, 2011, 02:35:27 pm

Gary, I agree with your views, it just amazes me that the filter engineers would not also have similar views on the other filters such as lube oil, guess it is too costly to have a restriction gauge in the lube filter line. Just thoughts, and for sure the K&N jab was for laughs.

Thanks for your experience and views

Re: Air Filter - Engine

Reply #44 – June 30, 2011, 02:39:18 pm

Gary, I used to do tech service in another industry and in one month I had the opportunity see more potential problems and solutions than a customer would see in an entire career. They didn't always listen to me and it always costed them money.

I hope everyone listens to your good advice. Granted, it is your opinion but it is a very educated opinion. Thanks for sharing your knowledge with us.

Re: Air Filter - Engine

Reply #45 – June 30, 2011, 02:45:28 pm

Quote from: Dick S – June 30, 2011, 01:13:16 pm

Gary, the local industrial supply house I use to buy filters told me "here in the NW where we have so much rain and moisture in the air, I recommend changing these air filters every year". He feels the moisture affects the paper.
What say you?

Dick,

To a degree, I do agree with them. Paper media filters can be affected by moisture. But that moisture level only becomes an issue when the paper is thoroughly wetted. On-highway vehicles generally have very poor water separating methods incorporated into the intake and housing designs. When paper media air filters become wet, the dust is washed out of the media into the engine. Changing more frequently does not make this matter better. Dry paper and keeping it dry is the best situation. I see that some MHs have the air intake situated very low, too low. Those systems pick up more road spray from their own tires as well as other vehicles. While impractical for most MHs, an elevated air intake to draw air near the top of the coach would be much better and also will prolong the air cleaner element life as most dust on highway is below that inlet. Have you ever noticed how farm tractors have a very high intake air stack, just below the exhaust stack? That elevation gets cleaner air from above the usual tire-generated dust clouds in the field.

The part about changing yearly really helps their bottom line.

Re: Air Filter - Engine

Reply #46 – June 30, 2011, 02:58:05 pm

Quote from: Dave M – June 30, 2011, 02:35:27 pm

Gary, I agree with your views, it just amazes me that the filter engineers would not also have similar views on the other filters such as lube oil, guess it is too costly to have a restriction gauge in the lube filter line. Just thoughts, and for sure the K&N jab was for laughs.

Thanks for your experience and views

Dave,

There are restriction gauges for fuel filters. The company that makes the Filter Minder(tm), Engineered Products has such devices. They measure the delta P (pressure drop) across the filter. They only work on suction filters as found on all Cummins, some Caterpillar primary (before the lift pump) filters and any other engine that utilizes suction filtration. I have never seen these on MHs but the Davco 382 fuel water separator system would be an excellent replacement for many fuel systems that use smaller spin-on fuel-water separators. DAVCO Technology, LLC

Several micron ratings are available for this fine filter system. I personally know of applications where this system has become the only fuel filter mounted on the suction side of the lift pump and capable of being the same level of filtration as the secondary (after the lift pump) filter. A really sweet feature of this product is that you can see the advancing fuel level as the filter plugs. When it is first installed, the clear housing is filled with fuel. Start the engine, and the fuel level falls to almost the bottom of the upper clear bowl. As that filter plugs, the fuel level climbs. Periodic checks of the fuel level will give you plenty of notice as to when the filter is to be changed. It is an easier filter to see the water accumulated, as well. It is an easy filter to change. There is a plastic (optional metal) wrench to remove the large black ring nut that holds the housing down. Simple cap on top to pre-fill the housing. I used to hate this product as our company had a competing product. Davco has become THE standard fuel water separator in over the road trucks. Replacement elements for this housing are easy to find with many aftermarket filter companies offering replacement products.

Re: Air Filter - Engine

Reply #47 – June 30, 2011, 03:05:56 pm

Quote from: Kent Speers – June 30, 2011, 02:39:18 pm

Gary, I used to do tech service in another industry and in one month I had the opportunity see more potential problems and solutions than a customer would see in an entire career. They didn't always listen to me and it always cost them money.

I hope everyone listens to your good advice. Granted, it is your opinion but it is a very educated opinion. Thanks for sharing your knowledge with us.

Absolutely agree, Kent.

Re: Air Filter - Engine

Reply #48 – July 02, 2011, 10:24:16 pm

You can search the archives for a photo of the fuel restriction gauge I added to my engine. I use it exclusively in deciding when to change fuel filters.

Re: Air Filter - Engine

Reply #49 – July 02, 2011, 10:32:33 pm

Brett,
I searched on FF for fuel restriction gauge and when I clicked on the link I was taken to a site that said I am not a member. Would this be the old Yahoo Forum?

If someone else finds the gauge, maybe they can post a better link.

George

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