Oil filter including an angled mounting surface

A liquid filter for mounting to a filter connecting flange of an internal combustion engine, the filter connecting flange including an outlet port and a threaded inlet aperture that passes through the filter connecting flange, the filter comprising:

• a filter housing including an open first end, a second end that is closed by a front wall, and a peripheral sidewall coaxially surrounding a central axis, a cover releasably attached to the open end of the housing, the filter housing and cover defining a filter chamber, the front wall comprising a central aperture and an inlet port spaced radially outwardly of said central aperture for alignment with the outlet port in said filter connecting flange, said front wall having an inner surface facing said filter chamber and a planar outer surface for mounting to said filter connecting flange;
• wherein an angle between said central axis and the planar outer surface of said front wall is less than 90.degree.;
• a hollow fastening screw extending axially through said central aperture for defining an outlet of said filter housing, said fastening screw comprising a head portion disposed in the filter chamber, said head portion including a collar bearing against the inner surface of the front wall, the fastening screw further comprising an externally threaded shank extending through the front wall, the externally threaded shank for threadably coupling with the threaded outlet aperture of the filter connecting flange to clamp the outer surface of the front wall of the filter housing to the filter connecting flange, and
• a filter cartridge disposed in said filter chamber between said inlet port and said outlet for filtering a liquid.