| 摘要 |
PROBLEM TO BE SOLVED: To suppress deterioration of engine fuel economy caused by a decrease in oil temperature when an engine is in a warm-up operation and an engine load is a high load condition, in an engine cooling device. SOLUTION: A pump control section 24b operates an electric pump 19 so that during warming up and in a no-load condition or a low-load condition, a cooling water circulation state is sequentially put in a circulation stop state and a first circulation state. Meanwhile, the pump control section operates the electric water pump 19 so that during the warming up and in a high-load condition, the cooling water circulation state is put in a second circulation state with a larger amount of cooling water circulated than the first circulation state. An oil cooler passage 22 with an oil cooler 31 disposed is provided in a cooling water circuit. The engine cooling device further includes: a cutoff valve 23 provided in the cooling water circuit; and a cutoff valve control section 24a closing the cutoff valve 23 during the warming up and in the high-load condition while opening the cutoff valve 23 during the warming up and in the no-load condition or low-load condition. COPYRIGHT: (C)2010,JPO&INPIT
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