1970 Chevrolet G30 Van Engine: 4.1L L6; Standard Rotation; Non-Thermal Fan Clutch; w/o A/C;. 1971 Chevrolet G30 Van Engine: 4.1L L6; Standard Rotation; Non-Thermal Fan Clutch; w/o A/C;. 1972 Chevrolet G30 Van Engine: 4.1L L6; Standard Rotation; Non-Thermal Fan Clutch; w/o A/C;.