Working machine engine starting system, engine and working machine

The utility model relates to the technical field of operation machinery, and discloses an operation machinery engine starting system, an engine and an operation machinery, the operation machinery engine starting system comprises a starting circuit suitable for being electrically connected with a starting motor of the engine; the relay switch is connected to the starting circuit in series; the pilot switch is electrically connected with the relay switch, is suitable for being connected to a hydraulic system control loop of the operation machine in series, and is suitable for disconnecting a starting circuit through the relay switch while sending a starting signal to the hydraulic system control loop; the relay switch sends a starting signal to the starting circuit and is suitable for disconnecting the hydraulic system control loop through the pilot switch. The relay switch is arranged in the starting circuit, the release voltage is low, the voltage fluctuation is reduced, and the starting success rate of the e