So, after all this time, starter motor is still goin strong, just. This was the unsealed test. While it has lasted since the last post it was substatialy dirtier inside having not been sealed up with silicone. Even though it has only been underwater once since then. I stripped it down again, sealed it up totally with silicone and sunk it. For a couple of hours just for fun. And the bell housing must trap an air bubble in it, as it was dry as hell inside. Conclusion, il be running it sealed up from now on. Id also note i have still replaced no parts on my starter yet.