Method and apparatus for filtering engine exhaust

A valve apparatus, comprising:

• a valve body including an opening;
• a movable cover;
• a plurality of axially aligned bi-metal discs attached to the cover, wherein the discs bow out and flatten axially as the temperature increases and decreases, thereby moving the valve cover to open and close the valve;
• a retaining spring for positioning the cover, wherein the bi-metal discs are positioned on a first side of the cover and the spring is positioned on a second side of the cover.

A filter apparatus for filtering exhaust gases from an engine, comprising:

• exhaust cooling means for cooling the exhaust gases prior to the gases from the engine;
• a removable and reusable pleated filter cartridge in a filter housing;
• and,
• temperature override means for directing exhaust gases away from the filter cartridge upon reaching a predetermined temperature comprising a plurality of axially aligned bi-metal discs positioned in the exhaust flow expanding axially as the temperature increases and a valve cover mounted to a moving end disc;
• and,
• back pressure release means for releasing the exhaust gases prior to filtering upon exceeding a predetermined pressure.

A filter apparatus for filtering exhaust gases from an engine, comprising:

• a replaceable filter cartridge for filtering the exhaust gases;
• and,
• a temperature sensitive override valve for redirecting the exhaust gases when a predetermined temperature is exceeded, the temperature override valve located proximate the filter downstream in the exhaust flow from the engine and preceding the filter cartridge, comprising:
• a valve body including an opening;
• a movable cover;
• a plurality of axially aligned bi-metal discs in a chamber defined by the valve body, wherein the discs bow out and flatten axially as the temperature increases and decreases;
• a valve cover slidably mounted in the chamber to an axial end of the discs, wherein the valve cover moves between a first position wherein the valve is open and a second position wherein the cover closes the opening when the discs bow out;
• a retaining spring for positioning the cover, wherein the bi-metal discs are positioned on a first side of the cover and the spring is positioned on a second side of the cover.