David Stricker wrote:

Paul,

Don't know if the group has seen these yet, but (K&N) makes oil
filters (and
other filters) that have a nut on the bottom with a hole in it
that could be
used for safety wire.

http://www.knfilters.com/

L David Stricker
Goodyear Arizona

David Arbogast wrote:

They also have a one-way valve that prevents drain back after
shut-down.
-dave

Most filters have an anti-drainback valve - even the pretty poor Fram.  And
many filters don't - including the Fleetguard LF9001 for the Cummins ISX
that I just turned into a teaching display.  The valve keeps the filter from
emptying and prevents a dry start, but also keeps the crud from the filter
from draining back into the engine.  A filter mounted on it's side or upside
down generally needs one; a filter that hangs down generally doesn't.

The best performing filter (per SAE testing - HS J806B and J1858)) that I've
seen on the shelf is the Mobil 1 at around $10 per.  The media isn't just a
paper 'coffee filter', it's a blend of cellulose and synthetics that
provides more solid holding and the ability to filter finer particles. The
average filter using a paper surface filter and hits the 50% efficiency
point with 40 micron contaminants.  A premium filter (AMSOIL, Mobil 1, Hard
Driver) gets into the 50% efficiency point at 20 microns, and generally hold
1.5-2 times the solids of a paper filter.  They're generally built with a
heavier can and a longer life gasket, which makes them the best choices for
extended drain intervals in 'normal' use, or best protection in 'extreme'
use.

Full flow filters are designed to filter all the oil all the time and
prevent immediate damage.  They're designed to catch all the 'rocks'.  To
slow engine wear, a filter has to be pretty efficient in the 5-20 micron
range (SAE papers 710813, 790089, 881825).  (Moving from 40 micron filtering
to 10 microns doubles the life of roller bearings and increases ball bearing
life 42%.  Needelman and Zaretsky 1991.)

Andy Hecker
San Antonio

 
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