Your drain tube may be stopped up with ice at the upper end because it drains too slow because it's stopped up at the lower end in the evaporator pan under the unit at the floor. It can get dust and mold in it. Once you get the ice out at the top a little air pressure will usually clear it out. Flushing it out with hot water and clorox may help. Make sure it drains quick enough. The drain should be located below the evaporator coils on the lower back of the freezer.
Part 7 is your drain>http://www.appliancepartspros.com/sect/x/w/y/xwyoykj0sa.gif

That was the problem. it looks like at factory they didnt flatten the medal piece around drain. mettle lip was sticking out just enough where water could just sit ther, off course it froze and caused the problem. thanks again