RE: K&N filter test -construction equipment

[John Cooper <jacques.noir@mho.net>]

Martin, you have done the Quattro List a great service by posting the note
about re-useable filters in dusty conditions.
The note you posted was originally posted in a Prodigy forum for
automobiles, which I stumbled on a few years ago.  Remarkably, many of the
forum participants still thought both the K&N and the popular filter system
used in the test: AMZOIL ,still worked.
My experiences with K&N filters comes from the motorcycle business where
most of the racers we sold them to let the filters get so dirty they
worked.  We never saw any dust in the carbs or intakes from racing.  
So I thought installing one on my Audi 200 tqw would be all that it was
advertised.  Added a little filter oil to the factory prepared element for
good measure.
After a year of driving around Colorado's dry and often very dusty roads, I
took the K&N off to clean it.  Also took off the entire air box which you
need to do.  Guess what.  The air tube  where the hot wire sensor is
located was coated in fine dust.  That filter no longer is part of my
garage and car parts inventory.  Went to the local autoparts store and
found a FRAM direct replacement made in Italy which had a huge amount of
pleats in the paper, much more area than the stocker.  It's been in place
now for another year and a half, same dusty conditions.  Last fall an
examination of the intake tract showed NO DUST at all.
Confirmation of your posted article test findings.
Folks that live in damp, strictly highway settings won't have the dust
problem.  But those of you using re-useable filter elements in dusty
conditions found in the West will regret having all that dust ingested in a
fine engine.
Coop