PURPOSE: To shorten the time required for starting an engine having a hydraulic type electronic timer, by providing an auxiliary hydraulic system operated independently of a main hydraulic system.

CONSTITUTION: An auxiliary hydraulic system 13 is provided independently of a main hydraulic system 3 for driving a hydraulic type electronic timer 2 which controls the fuel injection timing of an internal combustion engine, and the auxiliary hydraulic system 13 is connected operatively to a preheating means 20 which is set into operation at the time of starting the engine. When a switch 18 is operated at the time of starting the engine, the preheating means 20 is set into operation, and at the same time, a motor 17 is started for supplying oil from the auxiliary hydraulic system 13 to the timer 2. With such an arrangement, the fuel injection timing can be controlled to an optimum timing even at the time of starting the engine. Therefore, it is enabled to shorten the time required for starting the engine.