An experimental method is used to investigate suddenly applied imbalance responses of a flexible rotor with an uncentralized squeeze-film damper. The results show that the unstable transient process in this system is very short

and only after a few cycles the system recovers to steady state on new vibration level. The squeeze-film damper system has a limited capability of sudden subjection to the imbalance load. The limits depend mainly on the oil-film clearances of the damper. This work will be helpful for selecting squeeze-film parameters and experimental method of suddenly applied imbalance.