Where to train/quest for Engineering 240+?Follow

My engineering is maxed out at 240. I can not find a trainer to increase my skill. I have been told to go to Gadgetzan, but the trainer does not give me the option to train to increase my skill lvl. I was told there may be a quest but no one knows the name of this possible quest. I am stuck and frustrated with it and would appriciate some helpful advise.