Changed rear motor mount in 2001 oddessy after completion tried starting up and smoke was pouring from back side of engine. Rpms running at 2500 in parked position any ideas??

 

welcome to the forum. with little info, i will take a guess. due to engine mount change only, if the outside temp is cool, it could be condensation. if engine was warm and running at operational temp and smoke, valve guides, or piston oil rings failing. take your oil fill cap off and see if you have strong bypass air coming out if not valve guides worn. what is your milage, how often do you change your oil, how long has this been smoking (when engine is warm )