15 sportsman 850 starter staying engauged

Good evening all again!!! Got another problem that i need so imput a few weeks ago was having a problem with the starter intermitantly staying engauged while running it would start on its own without brake held and then starter would keep spinning. Took to my dealer and they replaced ignition switch it was fine til today yet again was out at AOAA in PA and just had gone threw water and a few minutes later on trail starter was engauging and would not turn off. Started quad again and pulled starter wire so would not burn out starter. Can anyone give me any suggestions on what the problem may be. CauseI am ready to call POLARIS and tell them to take this thing back.:disappointed: