[Chop]

Seriously? You keep your filter for 30,000kms? ill check mine when i dump the oil every 5000kms and either blow it out or replace it. For the coin, its nothing to change every 5-10 thou.

[pete_79]

That's from brand new, the first 10k were pretty much all on road.
We did dealer services for the first 15k just in case there was any warranty issues.
Once it was about 18 months old I started doing my own servicing every 5,000 - 8,000 (of course checking and blowing out the filter with ever service).

I noticed it was due for a change when I did my pre trip checks before the last trip, but was planning to do a service when I got home so let it go till now.

[J--A--C--K]

Blowing a filter out is almost certainly worse for your engine than not doing anything at all, and changing a filter that is still fine is also going to do nothing at best and more likely let contaminints in when you remove the otherwise fine air filter.

[Scrawny]

J--A--C--K wrote:

Blowing a filter out is almost certainly worse for your engine than not doing anything at all, and changing a filter that is still fine is also going to do nothing at best and more likely let contaminints in when you remove the otherwise fine air filter.

^^this^^

[atari4x4]

^^^ that

[Jezza86]

J--A--C--K wrote:

Blowing a filter out is almost certainly worse for your engine than not doing anything at all, and changing a filter that is still fine is also going to do nothing at best and more likely let contaminints in when you remove the otherwise fine air filter.

Actually prematurely changing filters is detrimental to engine life. Pm10 and pm2.5 meterial collected on filter surfaces improves filtration, and swaping filters too freaquently lets more ultrafines in

[pete_79]

Holy crap!
After all of ^^^^THIS and ^^^^^THAT, I can see that I have clearly destroyed every motor in every car I've ever owned. But I will never blow out another air cleaner ever again, I promise.

And just to be sure I've ordered one of these.
Now I'll know when it's exactly the right time to change the filter next time.

[J--A--C--K]

May not have destroyed an engine in the life of the car , but doing something that is more or less bad for an engine to some degree no matter how small, in the name of maintenance is a pointless exercise.

[Chop]

I forgot, Melbourne doesn't have dust

[greenzook89]

I just replaced the Filter in my Sierra for the first time in 3 years, I am still not convinced it required it at the time.


And don't get me started about changing Dirtbike Foam Filters

[Gwagensteve]

You'd be surprised how much dust we have Chop.

pete79 - you only need a telltale or a magnehelic gauge. Pretty simple.

Steve.

[Gwagensteve]

You'd be surprised how much dust we have Chop.

pete79 - you only need a telltale or a magnehelic gauge. Pretty simple.

Steve.

[Marko_SJ]

greenzook89 wrote:

I just replaced the Filter in my Sierra for the first time in 3 years, I am still not convinced it required it at the time.


And don't get me started about changing Dirtbike Foam Filters

Mine didn't seem to need it when I checked the condition of the airbox after reading this thread. So I stuck it back in and used silifella gasket where the worn rubber gasket was, after reading Gwagen's rant on how they don't seal (in truth, the rubber seal was actually U/S) .

[laurie]

I checked the air filter on the van today as 10k is nearly up .
we stopped here for a brew up on the way from Cameron corner to Tibbooburra
the van looked a little dusty in and out. ( i had a nice fake tan though )

The air filter was dirtier than i expected with the pre cleaner.

but glad I've got one.

[Jezza86]

so i was thinking about pre filters, and what the best pre filter design would look like, and i decided a good place to start is something that, by its very design, removes dirt from airflow.

so whilst being large, impractical and likely laugh worthy every time you pop the bonnet, i think a vacuum cleaner cyclone would be a reasonably good pre filter!

there's some obvious limitations, like the fact that a vacuum cleaner cyclone relies on a vacuum to get velocity,which in turn creates centrifugal forces that remove the dirt and dust from the airflow. this would have to limit WOT power but may also provide a catch cell in front of any filtration setup where larger items or water might be captured.

it is obviously a theoretical exercise, more optimization is possible by using higher effective surface area filters, and puting the air intake in a clean location, with existing spin top pree cleaners, but i thought i would share the madness anyway! it could have other applications it could be a great (cheep) pre cleaner for a small diesel generator or pump in a dusty location...

[Mike57]

Isn't that how the original Donaldson pre-cleaner works anyway and it is dimensioned for the correct air flow through the engine?

[Jezza86]

yep, but was tring to think of a way of makeing it under the bonnet, super small but cheap.

[Gwagensteve]

The Donaldson pre cleaner would be about as small as possible whilst still flowing enough air.

Steve.

[TEKNO]

When I had my M18A installed I was advised to buy a k&n filter as they supposedly flow better so I did and my car was set up and dynoed with it in situ and along with a piggyback ECU after a while of not running properly but after reading this whole thread it made a lot of sense about the use of OEM paper filters so yesterday I went and bought a stock air filter and it really is noticeable how lively my jimny feels now it really did make a difference in which I was surprised by.
So explain again please just why jim is more lively now than when it had the high flow filter in? And I thought paper filters had less flow hmmmph,I guess not huh

[Jezza86]

its possible the oiled K&N was likely blocked with accumulated dirt, but (honestly) its more likely your imaging the improvement.
there would be less than a Kw difference between the two filters (unless you were running a pod filter under the bonnet, in that case on a hot day you could be talking 2-3 Kw)

[TEKNO]

No not imagining in fact I checked the k&n as it was cleaned approx 7000 kms ago with the service and it still looked reasonably clean so I have been playing around with both filters and I put the k&n back in yesterday and noticed that it in fact it did seem a wee bit on the sluggish side but when I eventually reinstalled the paper filter it was most definitely more lively, I'm not talking mega horsepower but it feels crisper when driving if that makes sense,more responsive.
Also sometime ago I had a diesel vw golf and that had a k&n in it when I bought it and I drove it like that for sometime but i eventually installed a standard paper filter into that as well for reasons I don't recall now but I do remember that also went better and yes the oiled filter was maintained in that car too. I believe the manufacturers install paper filters for a good reason and that all of their r&d isn't just time wasting.....go figure

[Gwagensteve]

I genuinely believe you're imagining it Tekno. K&N Filters do actually flow more air than paper. That's part of the problem with them. If your experience was common, K&N wouldn't have the "good" reputation they do.

Any difference in flow (positive or negative) would be undetectable.

If you really want to test the theory get someone to swap (or not) the filter and no tell you which one is in the car. I bet you can't tell which filter is in the car.

[TEKNO]

Point noted Steve,my air box was modified also due to not enough airflow for the 1.8 as a liana airbox was never going to fit in the jimny but I think I will stay with oem type filters from now on

[henno]

I'm currently in the process of 'de-boganing' the new tow pig, and after peeling off my weight in fully sick Fusion and Alpine Star stickers, it was time for the K&N filter (and accompanying twenty-seven K&N stickers) to get in the bin. I'll leave this video of mine here, in lieu of a proper air filter rant:

[Gwagensteve]

Where is the like button?

[ozzycouch]

I changed an air filter once

[TEKNO]

Gwagensteve wrote:

I genuinely believe you're imagining it Tekno. K&N Filters do actually flow more air than paper. That's part of the problem with them. If your experience was common, K&N wouldn't have the "good" reputation they do.

Any difference in flow (positive or negative) would be undetectable.

If you really want to test the theory get someone to swap (or not) the filter and no tell you which one is in the car. I bet you can't tell which filter is in the car.

I actually read an email that said...
The negative impact usually associated with a loss in low end power is from an increase to intake volume. When you install a freer flowing after market air intake air will travel at a lower velocity until the positive effect of decreased friction loss overcomes the negative effect of a reduced velocity. So basically you lose bottom end and mid range power to gain a few HP on the top end.


I also read of a Lexus owner that had noticed the same loss of torque I have noticed in my Jimny.
Interesting stuff!!
Note. My fuckup for reading all my emails when tired
K&n said we are not sure why you are experiencing this but we have heard of it before.
Our filters will not increase hp but will flow much better than a standard type paper filter and that I can return it for a refund if I wish
That was what I expected

[Gwagensteve]

None of that makes any sense at all.

[Marko_SJ]

greenzook89 wrote:

And don't get me started about changing Dirtbike Foam Filters

Please start. My opinion got me crucified by many on Thumpertalk. Interested to hear yours.

[TEKNO]

Gwagensteve wrote:

None of that makes any sense at all.

Oddly enough,I thought the same also haha I guess I was hoping someone could explain it better than what I previously wrote.
I thought it was something to do with intake velocity???? Stuff knows but I do know after much reading that some others have had the same issues withe the k&n as I have had