Lubricating system for engine

摘要

A lubricating system for an engine comprises an oil pan for storing a lubricating oil therein, an oil cooler for cooling the lubricating oil, and an oil pump including first and second pump rotors contained in a casing. The oil pump is provided with a suction port commonly used for both the pump rotors, a first discharge port exclusively used for the first pump rotor and a second discharge port exclusively used for the second pump rotor. The suction port is in communication with the subsurface of the oil in the oil pan, the first discharge port communicating with an inlet port of the oil cooler, and said second discharge port communicating with the to-be-lubricated portions of an engine. A second suction port is provided in the casing of said oil pump to be exclusively used for the second pump rotor, and an outlet port of said oil cooler is connected with the second suction port, so that the entire amount of the lubricating oil passed through the oil cooler is supplied to the to-be-lubricated portions under the action of the second pump rotor.