Air filter element modification question.

[Vineboy]

While I was doing a routine service on my non turbo Triton I noticed on the air filter cartridge that the white plastic sleeve that covers the bottom half of the element was cracked so I pulled it off to fix it. It took me about a week or so to do this but in the meantime I noticed that power and fuel economy had got better. I was getting an extra 60ks per tank. 10% increase.

My question is: Can I leave this sleeve off as it appears to be blocking half the element from doing it's job?

Cheers,
Andrew.

[superzuki]

any pics of it.... aslong as it doesnt let any unfiltered air to pass i dont see any problem. apart from blocking the filter does that white sleeve do anything

[HotFourOk]

Does it have fins on the plastic sleeve also?

My Rocky has these standard also, I removed it when I relocated my air intake for the Snorkel. I also think it decreases the amount of usable element. It might be meant to swirl the air to remove foreign particles?

[KiwiBacon]

10% would be a red herring. Try a few more tanks and see. It would take an almost completely blocked filter to make an engine suffer that much.

It's there to spin the heavy stuff out of the airflow, thus keeping your filter cleaner for longer. Without it you'll get dust clogging sooner.

[Vineboy]

Here it is with the sleeve off. Whenever it gets really clogged up the part with the sleeve on is clean which makes me think it's not doing anything anyway. I know it's supposed to set a swirl to throw off bigger objects but I think I can do without it.

[ISUZUROVER]

Removing it would give you slightly less pressure drop through the filter (so slightly more airflow/power) - but like Dougal I doubt the 10% claim.

HOWEVER - the integral cyclonic pre-cleaner (which that is) removes about 50+% of the MASS of dust entering your intake. SO -0 if you remove it, you will shorten filter lifespan by 50% or thereabouts.

But if you mainly drive on the road, and change the filter every 20k km, then you are changing the filter far too often anyway, so may as well remove it.

[MightyMouse]

If it swirling off dust etc then the dust should end up in the air cleaner housing...

If its full of crap then it works for your type of driving, if the housings clean inside then for you it isn't doing that much so you can consider tossing it.

And a 10% gain is pretty substantial - are you certain ?

[ISUZUROVER]

If it swirling off dust etc then the dust should end up in the air cleaner housing...

If its full of crap then it works for your type of driving, if the housings clean inside then for you it isn't doing that much so you can consider tossing it.

And a 10% gain is pretty substantial - are you certain ?

Some housings have a valve that dumps this dust out when you turn the engine off - so not always possible to see the amount of dust being removed.

[MightyMouse]

Ok - i didn't know that...... Still would expect to find some evidience but haven't looked enough to see the type of system your talking about.

what vehicle were fitted with this ?

[KiwiBacon]

Ok - i didn't know that...... Still would expect to find some evidience but haven't looked enough to see the type of system your talking about.

what vehicle were fitted with this ?

Pretty much every donaldson system I've seen. They a short pipe heading downward with a rubber lip cover on them. They work as a one way valve to let dust fall out but not let air get sucked up through it.

I guess taping a plastic bag loosely over that would show it working by collecting the dumped dust.
I made my own filter housing with a scroll shape and just left a small hole at the lowest edge. It's surprising what gets dumped out that hole.

[Vineboy]

Car is a 1998 MK Triton 2.8 non-turbo with no snorkel. I have quite put a few tanks through it and getting about 60ks extra or thereabouts. Usually I get about 600ks out of a tank so the 10% (give or take) claim I'll stick by.

Power wise it feels like there is more power but who knows. Face it, I need all the power I can get from this engine. Always late in a 2.8.

There is a little flap on the bottom of the housing which gets a bit of crap in it.

[Gee]

I've got a non-turbo 4M40 triton. I use a reusable foam Finer Filter and have so for about 3 years without any dramas (and that includes regular driving in very dusty conditions in NW Qld). There is no plastic casing like with the paper filters so I would happily ditch it. Even better so, buy a Finer Filter. Mine cost $95 (including a bottle of oil) and when you consider that the paper filters were costing me around $40-$50 each, it has paid for itself many times over and will keep on doing so as long as I own the vehicle.

[Rockwolf]

Gee, the only thing I'd note is that some aftermarket filters (K&N, I'm looking at you) provide better flow by reducing the amount of filtering done. I don't know if that's the case with the Finer Filter (never seen one), but airfilters are cheap compared to a rebuild.

[ISUZUROVER]

I've got a non-turbo 4M40 triton. I use a reusable foam Finer Filter and have so for about 3 years without any dramas (and that includes regular driving in very dusty conditions in NW Qld). There is no plastic casing like with the paper filters so I would happily ditch it. Even better so, buy a Finer Filter. Mine cost $95 (including a bottle of oil) and when you consider that the paper filters were costing me around $40-$50 each, it has paid for itself many times over and will keep on doing so as long as I own the vehicle.

Might want to read the threads on reusable filter options before buying one. Finer filters are probably better than average, but I am giving my (hilux) FF away to anyone who wants it and going back to a cellulose (paper) filter. They are better.

Btw - I kept the plastic pre cleaner when I fitted my FF years ago. As I said, it stops at least 50% of the dust from getting to the filter.

[Gee]

The finer filter has an inner and outer section of foam (together both sections of foam are around 30-40mm thick). I usually have a close look at the condition of the filter before cleaning and re-oiling (the oil is similar in consistency to honey and sticky as). I have always found the inner layer of foam to be in the same condition as when I first put it in. The inside metal frame of the filter is also clean and free of any traces of dust. This is good enough for me.

I agree that not all reusable filters are a good idea. I would never touch a K&N (especially if you plan on driving on anything other than clean sealed racetracks) and I am not so confident I would even use a unifilter- makers of finer filter (I think they only use one section of foam). I think if you clean and oil the finer filter correctly and regularly (I do it every 5000k's) you should have no problems.

[ISUZUROVER]

The finer filter has an inner and outer section of foam (together both sections of foam are around 30-40mm thick). I usually have a close look at the condition of the filter before cleaning and re-oiling (the oil is similar in consistency to honey and sticky as). I have always found the inner layer of foam to be in the same condition as when I first put it in. The inside metal frame of the filter is also clean and free of any traces of dust. This is good enough for me.

I agree that not all reusable filters are a good idea. I would never touch a K&N (especially if you plan on driving on anything other than clean sealed racetracks) and I am not so confident I would even use a unifilter- makers of finer filter (I think they only use one section of foam). I think if you clean and oil the finer filter correctly and regularly (I do it every 5000k's) you should have no problems.

Foam has MUCH larger (equivalent) pore sizes than cellulose media (paper filters). The sticky FF oil does nothing apart from stop rebound (bounce) of impacting particles. Since the foam is very soft (is able to elastically deform to absorb particle impacts), it is likely to be quite good at resisting particle bounce. the value of the oil is therefore dubious, especially as it partially blocks the filter, creating a higher interstitial velocity.

Just because you can't SEE dust on the inner element doesn't mean it isn't there. The human eye can only see down to about 20-30 microns, and particles much smaller than that can damage engines. The dust you are seeing on the outer band would mostly be larger particles (hundreds of microns).

However - I agree that it would still be better than a K&N, but not better than a good quality paper element. Unlike the manufacturers claim, in conventional (foam/cellulose) media, filtration efficiency and pressure drop are proportional - so you can't have a filter that flows better AND has better filtration efficiency (unless the high pressure drop is caused by non-media factors (like the plastic pre-cleaner sleeve)).

[Gee]

The finer filter has an inner and outer section of foam (together both sections of foam are around 30-40mm thick). I usually have a close look at the condition of the filter before cleaning and re-oiling (the oil is similar in consistency to honey and sticky as). I have always found the inner layer of foam to be in the same condition as when I first put it in. The inside metal frame of the filter is also clean and free of any traces of dust. This is good enough for me.

I agree that not all reusable filters are a good idea. I would never touch a K&N (especially if you plan on driving on anything other than clean sealed racetracks) and I am not so confident I would even use a unifilter- makers of finer filter (I think they only use one section of foam). I think if you clean and oil the finer filter correctly and regularly (I do it every 5000k's) you should have no problems.

Foam has MUCH larger (equivalent) pore sizes than cellulose media (paper filters). The sticky FF oil does nothing apart from stop rebound (bounce) of impacting particles. Since the foam is very soft (is able to elastically deform to absorb particle impacts), it is likely to be quite good at resisting particle bounce. the value of the oil is therefore dubious, especially as it partially blocks the filter, creating a higher interstitial velocity.

Just because you can't SEE dust on the inner element doesn't mean it isn't there. The human eye can only see down to about 20-30 microns, and particles much smaller than that can damage engines. The dust you are seeing on the outer band would mostly be larger particles (hundreds of microns).

However - I agree that it would still be better than a K&N, but not better than a good quality paper element. Unlike the manufacturers claim, in conventional (foam/cellulose) media, filtration efficiency and pressure drop are proportional - so you can't have a filter that flows better AND has better filtration efficiency (unless the high pressure drop is caused by non-media factors (like the plastic pre-cleaner sleeve)).

Dang, you know airfilters. Anyway I choose to be ignorant and I'll stick with my FF

[Gee]

For anyone wondering what a Finer Filter looks like:

[ISUZUROVER]

Dang, you know airfilters.

Well I would hope so - worked in filter R&D for a while now...

[MightyMouse]

A minor hijack isuzurover.....

I run an oiled foam precleaner "sock" in the snorkel and it picks up heaps of dirt - to the point that my main paper filter stays "visually" clean.

However from what your saying there will be "invisible" particles caught by the paper filter that will be progressively clogging it. Apart from manometer readings is there a simple way of checking a paper filter for blockage by these small particles.

And BTW is reverse blowing with compressed air effective at removing these particles ?

[Frankenyota]

Does the plastic sleeve make up the seal for the bottom of the filter?
In my hilux the plastic has a rubber seal on the bottom to seal the filter in the housing.
So maybe just cut the rest away and leave the seal there.

Matt

[ISUZUROVER]

A minor hijack isuzurover.....

I run an oiled foam precleaner "sock" in the snorkel and it picks up heaps of dirt - to the point that my main paper filter stays "visually" clean.

However from what your saying there will be "invisible" particles caught by the paper filter that will be progressively clogging it. Apart from manometer readings is there a simple way of checking a paper filter for blockage by these small particles.

And BTW is reverse blowing with compressed air effective at removing these particles ?

The precleaner sock is removing particles that would otherwise be trapped by your air filter. So the overall lifespan of the filter will be significantly extended. The dust you are collecting will probably be trapped deeper in the filter, but you will probably only get "clogging" when the filter is visibly dusty on the surface.

Contary to popular belief - filters are NOT SIEVES, the pore diameter is MUCH larger than the particle size a filter can collect. The particles the filter collects don't pack together densely, they have 70% porosity minimum, so they themselves then act as a filter, and trap further particles. So your air filter works BEST when it is dusty. No need to change it until the manometer says so.

[Vineboy]

On some trucks and bigger tractors you see the little manometer guages. Can we fit these to our rigs as well? If so where would you put the two sides?

[KiwiBacon]

On some trucks and bigger tractors you see the little manometer guages. Can we fit these to our rigs as well? If so where would you put the two sides?

I got a resettable vacuum indicator off a small donaldson aircleaner housing. I just welded a bung onto the steel pipe leaving the airfilter box and threaded it in there.

[Gwagensteve]

Leave the sleeve on. It sets up a vortex in the air filter housing, throwing dust to the outside of the housing and keeping your filter cleaner. All canister type airfilters use this kind of thing to improve the efficiency of the filter.

As an aside are you sure the element still seals with the sleeve removed?

Steve.

[MightyMouse]

Thanks ISUZUROVER, I have somewhat of an obsession with aircleaners, IMO many people don't understand the damage that can be done by poor filters.

IIRC some of the older diesel cruisers had a differential pressure switch fitted to their air cleaners. A bit of work to fit and wire but.......

[bazzle]

All around the aircleaner whee the white plastic bit is the pleats are still open to the air so unless there is that much airflow I doubt any change will be made. ie. the air still enters that section fron the periphery. /\/\/\/\/\/\/\/\/

Bazzle

[Vineboy]

Leave the sleeve on. It sets up a vortex in the air filter housing, throwing dust to the outside of the housing and keeping your filter cleaner. All canister type airfilters use this kind of thing to improve the efficiency of the filter.

As an aside are you sure the element still seals with the sleeve removed?

Steve.

Yep. It has a foam O ring seal which is seperate to the sleeve which I made sure is in place.

[zagan]

Here it is with the sleeve off. Whenever it gets really clogged up the part with the sleeve on is clean which makes me think it's not doing anything anyway. I know it's supposed to set a swirl to throw off bigger objects but I think I can do without it.

You flip the filter over to the clean side, maybe the dirty side is too clogged up and you need to flip to the clean half.

The bucket filters are the same deal simply turn the filter around to the clean half to get some extra filter time.

[zagan]

For anyone wondering what a Finer Filter looks like:

In Australia they are only known as uni-filter.

Finer Filter is the exporter name.

same company, I'm going to pick up one of their packs, very soon.