In a message dated 7/30/2006 11:49:36 A.M. Eastern Daylight Time,
MJRAGUSE@xxxxxxx writes:
If paper
elements didn't work, the 150,000 to 200,000 + engine would not exist and they
frequently do today. Other opinions
please?
I HEARTILY agree with Marv. One of the jobs I had while working
at the Chrysler fuel Systems Lab in the 1953-1961 era was testing air cleaners
for efficiency. This was during the transition from oil bath, to foam, to
paper filter media.
We (The automobile industry) used Arizona desert dust ground to specific
particle sizes for test material. The material was fed into the air
cleaner while we varied the airflow and measured restriction until a failure
occured.
Oil bath filters were 65-75% efficient, and would eat prodigious amounts of
dust and keep on going. They were, however, difficult and messy to clean
and service. Airflow ability remained high and lasted for a very long
time.
The oil-wetted foam filters were only about 60% efficient, and cheaper to
make. Airflow varied dramatically because of the small surface area of the
filter. They were nothing more than a "tent" over the carburetor.
Unfortunately, the more dust removed from the air, the lower their ability to
flow air, and if not frequently serviced, they would "collapse" and dump gobs of
muck into the carburetor. They were nothing more than a disaster waiting
to happen.
Pleated paper filters, however, started out life with a filter efficiency
of over 98%, and early in service life actually increased to over 99% when the
dust filled some of the pores. They would then slowly become more
restrictive until they eventually needed replacement. They were much more
sturdy than foam ones and did not catastrophically fail. since the
carburetors used at the time were internally vented, the fuel mixtures did not
get any richer. The flow rates would just reduce and eventually power
would be lost.
Joe
Savard
Lake Orion, Michigan