VARIABLE CYLINDER ENGINE

PROBLEM TO BE SOLVED: To execute a cylinder-reduced operation with an excellent fuel consumption performance in a wider load area.SOLUTION: An engine comprises: an engine body 1 having plural cylinders 2; a cooling mechanism 30 for cooling the engine body 1; and control means (50) that can cool the cooling mechanism 30 and change the operation number of the cylinders 2 according to the operation status. The control means (50) reduces the operation number of the cylinders in a cylinder-reduced operation region A set in a partial load area of the engine, and sets cooling ability of the cooling mechanism 30 in a first cylinder-reduced area A1 set to a high load side in the cylinder-reduced operation region A higher than that in a second cylinder-reduced region A2 set to a low load side in the cylinder-reduced operation region A.