the most important functions of motor oil is to capture and suspend
contaminants and wear particles, preventing premature wear on an engines'
internal parts. Acting alone, motor oil would quickly become saturated with
these contaminants and wear materials and would require very frequent
changing, perhaps as often as every 500 miles, in order to effectively guard
against wear. An engine's oil filter allows motor oil to last for an extended
period of time.
The earliest automobiles had no
oil filtration, and it was common to change oil every 500 to 2,000 miles.
Later, as pressure lubrication became standard on automobiles, some kind of
oil filtration was necessary to protect the oil pump from damage and wear.
Early designs were primitive, often consisting of nothing more than steel
wool, wire meshes or screens placed in the oil pump intake. Many designs were
cleanable and reusable.
The earliest incarnation of the
modern oil filter came about in 1923, when Ernest Sweetland introduced his
invention knows as the "Purolator," a combination of the words
"Pure Oil Later." Incorporated into the lubricating system after
the oil pump and before the oil flows into the engine bearings, the original
Purolator featured an upright series of seven twill weave cloth-covered,
perforated plates encased in a heavy-duty cast container. It also had a sight
feed glass on one side, enabling the owner to see the oil flow and change the
filter when flow slowed to a trickle.
James A. Abeles saw enough
potential in the Purolator to convert a New York City garage into a company called
Motor Improvements Inc., developed primarily to manufacture Purolator
filters. The Maxwell Chalmers Company also saw promise in this new product,
installing a Purolator on a Maxwell automobile which was test-driven on a
round-trip from Detroit to the West Coast in 1924. The
longer oil drain intervals, cleaner oil and reduced engine wear offered by
the Purolator ensured endorsement by the automotive industry, and they soon
became standard on many popular automobiles of the day, including Studebaker,
Pierce Arrow, Hupmobile, Peerless, Cadillac, Oakland, Gardner, Moon, Jordan,
Buick and Dodge.
Oil filter technology continued
to progress over the years. In the late 1930s, cotton waste material was
introduced as filtration media, providing the first filter
capability. Various woven fabrics were also used in some filter designs. By
1946, as disposable filter models became the norm and interest in saving
production costs increased, materials such as pleated paper and cellulose
became the filtration media materials of choice, materials that are still
widely used in today's oil filters.
Prior to 1943, most oil filters
were the "by-pass" variety, only filtering about 10 percent of the
oil at a time. The first "full-flow" oil filter, capable of
filtering 100 percent of the motor oil, was introduced in 1943 and became standard
on mass production vehicles by 1946.
The modern disposable
"spin-on" oil filter design was introduced in 1955, replacing
"cartridge-type" filters which had to be placed in a special
housing or canister. The technology progressed throughout the 1960s and
spin-on oil filters soon became standard on virtually all American, European
and Japanese automobile designs.
Today's spin-on filters resemble
metal cans that encase the filtration media, which capture and hold the
various organic and inorganic contaminants and wear metals within the motor
oil. Organic contaminants include bacteria and other organisms that make up
sludge, which inorganic contaminants include dust and dirt.
engine's oil pump pumps motor oil from the oil sump to the oil filter. Dirty
oil passes through the oil central tube and back to the engine through the
mounting stud. Oil is then distributed by oil passages throughout the engine.
BY-PASS OIL FILTERS
Secondary by-pass oil filters act separately from an engine's full-flow
filter and only filter a small portion of the oil in a system at a time,
subjecting it to additional and more thorough cleaning than the full-flow
filter is able to provide.
Various styles of by-pass
systems exist on the market today. Some feature centrifuge or thermal action,
spinning or boiling out contaminants, while others feature extremely
efficient media that remove smaller contaminants. Originally marketed as a
way to effectively extend equipment life, by-pass filters are also effective
in keeping oil clean and capable of extended drain intervals.
THE AMSOIL ADVANTAGE
As previously mentioned, many of today's conventional oil filters make use of
pleated paper or cellulose as their filtration media. Although these filters
usually display good flow characteristics when new, they tend to become
obstructed fairly quickly. In addition, these conventional filters exhibit
limited capacity, longevity and ability to catch fine particles.
AMSOIL Super Duty Oil Filters
(SDF) are designed for maximum efficiency, capacity and longevity, while
meeting the high flow demands of modern engine designs. In fact, with its
advanced filtration media composed of a special cellulose, synthetic and glass
blend, AMSOIL SDF Oil Filters have over a 75 Percent better combined
efficiency/capacity rating than other popular oil filters as tested according
to industry standards. AMSOIL SDF Filters are designed for extended drain
intervals of 12,500 miles or six months (whichever comes first), making them
ideal for use with premium AMSOIL Synthetic Motor Oils.
AMSOIL BY-PASS FILTRATION
Advanced engine designs place tough demands on an engine's full-flow filter,
most of which are capable of efficiently filtering out only coarser wear
particles, generally greater than 20 to 25 microns. However, approximately 60
percent of engine wear is caused by particles in the 5 to 20 micron range.
These tiny particles closely match the precision clearances between critical engine
components, entering the spaces between bearings, rings and other components
and damaging metal surfaces, altering tolerances, fatiguing components and
generating additional debris. For the ultimate in filtration efficiency and
wear protection, AMSOIL offers the Spin-On by-pass Oil Filter.
The AMSOIL By-Pass Oil Filter
provides the best possible filtration on the market, protecting against wear,
oil degradation, rust and corrosion. Situated outside the main line of oil
circulation, the AMSOIL
By-Pass Filter works in
conjunction with the full-flow filter, thoroughly filtering 10 percent of the
oil at a time and removing wear-causing contaminants down to less than one
micron in size. The AMSOIL By-Pass Filter effectively filters all the oil in
a six quart system in about 5 minutes at an average speed of 45 mph.
Water enters motor oil as a
combustion by-product or as a condensate. When it contaminates motor oil, it
can cause serious engine damage by causing metal surface rust and corrosion,
which increases friction and wear and deteriorates the close-fitting
tolerances between engine components. It can also react with other
contaminants to form corrosive acids, which also damage metal components. The
AMSOIL By-Pass Filter effectively removes up to a pint of damaging water,
significantly increasing the time oil can be safely left in the engine.
The effectiveness of AMSOIL
By-Pass Filter lies in its construction. Its high-capacity filtration medium
is a special blend of virgin wood and cotton fibers, formed into discs,
stacked and compressed. The center tube is all-steel, perforated for oil flow
and wrapped with a fine mesh cotton screen. Each filter includes a mounting
unit with a spin-on filtering cartridge, connected by hoses to engine ports.
Particles sized down to less than one micron are trapped an removed, while
the filter's thirsty cellulose fibers remove water.
BY-PASS FILTER ACCESSORIES
The AMSOIL Dual Remote Oil Filtration System allows an AMSOIL Super duty Oil
Filter and an AMSOIL Spin-On By-Pass Filter to be attached onto a remote
mount, providing easy access for both filters. Remote placement of the Dual
Remote system allows larger oil filters to be used and increased oil sump
The AMSOIL Dual-Gard Filtration
System links two AMSOIL By-Pass Filter elements together for engines with
sump capacities greater than 20 quarts.