In this investigation, fluid film damper is used for solving unexpectedly vibration phenomena, which was happened in air-breathing engine ground testing. Squeeze film damper, one kind of oil film damper, is vital for reducing the engine vibration and rotor shaft unbalance. It has already been applied in this kind of engine, however, the unexpected vibration still existed in the ground testing. In order to reduce the unbalance force, several treatments, for lower unbalance, are used for correcting vibration problem. Nevertheless, experimental results indicate the improvement is limited. However, with coating solid lubricant for enhancing squeeze film damping, which significantly decreases vibration problem. This study successfully provides an effective method to enhance the function of damper.