At least an embodiment may provide a remote server that can predict overheating of an engine. A remote server may receives an engine rotational speed, an engine load factor, and a cooling-water temperature. The remote server calculates a moving average of the engine load factor during a predetermine time, and calculates a correlation between the moving average of the engine load factor and the cooling-water temperature. If the correlation during a predetermined period is in the status of a predetermined difference from the correlation up to the predetermined period, the remote server predicts occurrence of overheating in a swing working vehicle that is used by a user.