I need help I have a proboat apache 24 all stock I installed a 550 Titan motor 12 turn and it fried , I than installed a gruenper 600 bb and it fried after about a half battery , I than installed a 17 turn double and it fried after 1 full battery . I'm running a 2 cell battery 25c 4000 mah so I'm not running too much voltage . The prob is stock I'm guessing i have to prop down but what size.? The shaft is free and well lube so I know there isn't any binding.