Abstract: An oil filter assembly is disclosed for a machine, such as an internal combustion engine, that has an oil output port and an oil input port. A mounting plate is fixed with an outer enclosure. The mounting plate is further adapted to conduct oil from the machine into a peripheral portion of the outer enclosure, and then returning oil from a central portion of the outer enclosure back to the machine. Oil may pass from the peripheral portion to the central portion through a primary filter having a first porosity. A pressure-actuated valve is fixed fluidly between the portions of the outer enclosure.

Abstract: An oil filter assembly is disclosed for a machine, such as an internal combustion engine, that has an oil output port and an input port. A mounting plate is fixed with an outer enclosure. The mounting plate is further adapted to conduct oil from the machine into a peripheral portion of the outer enclosure, and then returning oil from a central portion of the outer enclosure back to the machine. Oil may pass from the peripheral portion to the central portion through a primary filter having a first porosity. A pressure-actuated valve is fixed fluidly between the portions of the outer enclosure. Oil passes through the pressure actuated valve only when an oil pressure differential between the peripheral and central portions exceeds a threshold pressure. A secondary filter has a second porosity greater than the first porosity, and is fixed between the pressure-actuated valve and the central portion.

Abstract: A method for exchange of a filter assembly is described, wherein a contaminated filter assembly is exchanged for a refurbished filter assembly or a new filter assembly.

Abstract: An oil filter assembly is disclosed for a machine, such as an internal combustion engine, that has an oil output port and an oil input port. A mounting plate may be fixed with an outer enclosure and may be adapted for securing to the machine. The mounting plate may be further adapted to conduct oil from the machine into a peripheral portion of the outer enclosure, and then returning oil from a central portion of the outer enclosure back to the machine. Oil may pass from the peripheral portion to the central portion through a primary filter having a first porosity. A pressure-actuated valve may be fixed fluidly between the peripheral portion and central portion of the outer enclosure. Oil may pass through the pressure-actuated valve only when an oil pressure differential between the peripheral portion and the central portion of the outer enclosure exceeds a predetermined threshold pressure.