Multi-stage blow-by gas filtering for internal combustion engine

A method of filtering oil from a blow-by gas of an internal combustion engine, the method comprising:

• passing the blow-by gas from a crankcase of the internal combustion engine to an assembly that includes a first oil separating apparatus and a second oil separating apparatus;
• separating an initial amount of oil from the blow-by gas with a first coalescing filter within the first oil separating apparatus;
• passing the blow-by gas from an outlet of the first oil separating apparatus directly to an inlet of a second oil separating apparatus;
• separating a second amount of oil from the blow-by gas with a second coalescing filter within the second oil separating apparatus;
• and
• passing the blow-by gas from the second oil separating apparatus back to the crankcase.

An assembly for separating oil from a blow-by gas of an engine comprising:

• a first oil separating apparatus comprising:
• an outer housing;
• a first coalescing filter configured to separate an initial amount of the oil from the blow-by gas positioned within the outer housing;
• a first cover connected to at least the outer housing at a first end portion thereof, wherein the first cover has one or more inlet ports in fluid communication with a first cavity, wherein the first cavity is in fluid communication with the first coalescing filter;
• and
• a second cover connected to at least the outer housing at a second end portion thereof, wherein the second cover has one or more outlet ports in fluid communication with a second cavity, wherein the second cavity is in fluid communication with the first coalescing filter;
• a second oil separating apparatus comprising:
• a second outer housing;
• a second coalescing filter configured to separate a second amount of the oil from the blow-by gas positioned within the second outer housing;
• a third cover connected to the second outer housing at a first end portion thereof, wherein the third cover is in fluid communication with the second coalescing filter via a third cavity, and wherein the third cover is positioned adjacent but is separated from being in fluid communication with the first cover;
• and
• a fourth cover connected to the second outer housing at a second end portion thereof, wherein the fourth cover has one or more inlet ports in fluid communication with the one or more outlet ports of the second cover, and wherein the fourth cover has a fourth cavity in fluid communication with at least both the second cavity and the second coalescing filter.