Thread: The Air Filter Poll

Originally Posted by isuzurover

That may be even better - if you can give me a donaldson one with 20k worth of crap in it too. If we want to be really ambitious - we can test a new/clean one of each too (so we have a test of each filter at the beginning and end of its life/use) - if SSmith will clean and oil his then post it. I can return all filters in basically the same condition they were sent (if desired).

easy peasy. Have one sitting in a box as it was removed from the beast back in February. Had done 15-20000km. It was only removed as I seemed seemed to be getting higher than normal EGT's on a shopping trip to Tamworth, so ducked around to Cummins and slotted in a new Fleetguard (couldn't get a Donaldson on a Saturday). Turned out to be high ambient....

isuzurover
have a cleaning kit for the k&n, happy to put it to a better cause than killing my engine

I fitted the finer filter when I noticed while servicing the Disco (300tdi) at 190000 the seal around the edge was sliced along the rear edge.

I replaced the filter (with a Baldwin) as you would and checked it weekly and after 3 weeks noticed that it was also cracking so I had a look at why it may be doing it and noticed that it was hitting the snorkle inlet so I cut a relief into the inlet pipe so the filter would fit and fitted a Ryco,

Also lasted 3 weeks. In talking to a mate he suggested I fit an original LR Filter so I did that too.

It lasted about 2 months until it too started to crack so I fitted the Finer filter as they have a steel outer and are a triple oiled foam filter.

As far as dust filtration, it doesnt get past the first layer in 20000km's when I clean the inner filters. I clean the outer filter every couple of thousand km,s which turns black and when you wash it out there is heaps of dirt in the bottom of the tub.

When you wash out the inners there is no dirt in the tub.

It was money well spent.

I run a Ram air filter (Like k&N ) in the standard 90 housing . But change for a paper one when going off road as the ram air and K&N don't work very well with dust. Used the paper for going around Aus.,

Originally Posted by mcrover

As far as dust filtration, it doesnt get past the first layer in 20000km's when I clean the inner filters. I clean the outer filter every couple of thousand km,s which turns black and when you wash it out there is heaps of dirt in the bottom of the tub.

This is a phurphy - however most people believe it "I can't see any dust after the filter so dust isn't getting past it".

People used to think that dust (and wear/soot) particles had to be larger than your smallest engine tolerance to do any damage. However research in the US has provenn that this is not the case, and even very small soot particles (much smaller than engine tolerances) can do damage.

The human eye can only see down to about 30 microns - and particles much smaller than this can do a lot of engine damage. Also, particles have to be pretty big to settle or impact on the ductwork after the filter - and fairly large and in a high concentration to leave any deposit on the filter which you can see/feel.

Filters are not sieves - they often do not remove ALL particles of a certain size, and ALL air filters have a region (usually between 1 and 0.1 micron) where they are not very effective at removing particles (this is due to physics which I won't go into now) - so unless the filter is very efficient, you will be getting a lot of particles in this size range into your engine.

It MAY be that finer filters are better than K&N - if someone has one (for a 300Tdi to keep things consistent) they want to lend to me for the duration of the test I would be happy to test it as well as the K&N filter.

I am on the debate of getting either the K&N or the finer filter, would be interested to find out which one is the better of the two.

looks like it's time to post a link to Spicers filter test results on GM Duramax filters in the US again.
http://home.stny.rr.com/jbplock/ISO5011/SPICER.htm
Bear in mind that when looking at these results not to get hung up on how each brand of cellulose media performed relative to each other in this particular test as suppliers for individual applications within one brand often vary, look more at how the different types of media compare to each other.

[quote=rick130;528943]
http://home.stny.rr.com/jbplock/ISO5011/SPICER.htm
quote]

isnt that interesting.