Oil gushes out of breather filter when machine stops

I have an Ingersoll Rand MH45 air compressor, the E.motor got burnt due to overload, the E.motor was dismantled from Air end, Recoiled and coupled back.Machine runs well when turned on but when stopped, the E.motor runs in backward direction and machine gushes OIL out from the BREATHER FILTER. Please what could be the problem. we have done a solo test to confirm direction and it was found OK. Thanks as await your response THANKS