Water-cooled internal combustion engine for motor vehicles, particularly a diesel engine

Claim 1

An internal combustion engine with reduced noise level cooling system for a motor vehicle which comprises a water cooled internal combustion engine mounted on the frame of the motor vehicle, said engine having a drive shaft extending therethrough; a first cooling unit mounted directly in front of said engine, said first cooling unit including a first radiator through which cooling water from said engine passes and a first fan mounted for rotation between said first radiator and said engine; drive means mechanically connecting said first fan with said drive shaft so as to rotate same, said drive means including a first temperature-sensitive transmission device which allows said drive shaft to rotate said first fan when the cooling water flowing through said engine and said first cooling unit exceeds a first predetermined temperature; a second cooling unit mounted adjacent said first cooling unit, said second cooling unit including a second radiator through which cooling water from said engine passes and a second fan, said second radiator and second fan having smaller dimensions than said first radiator and first fan, respectively; and auxiliary means mechanically connecting said second fan with said engine so as to rotate said second fan, said auxiliary means including a second temperature-sensitive transmission means which allows said engine to rotate said second fan only when a second predetermined temperature of said cooling water passing through said engine and said second cooling unit is exceeded, i.e., when said first cooling unit is inadequate to dissipate heat generated by said engine, said first cooling unit being capable of dissipating at least 60% of the maximum heat output of said engine.