Hi folks! Can someone help me out? I was asked to undo the oil-sump-plug on my mates cinquecento. After trying to undo the the 12mm allen key nut, the whole plug came loose [washer type sleeve that the sump nut goes into]. After draining the oil out. I tried to see if the whole sump plug sleeve would fit in. It does but it's loose and when oil is put back in it drips out. It wont tighten up. Does anyone know if this can be repaired without having to re-fit a whole new sump casing? Thnaks