The only way water would go into the tank with that setup is if it sinks completely with it right side up. Even then, your going to have to do some serious work to it and pumping out the gas is a given. If it just rolls over, no water will enter the tank, because there will be no vacuum upwards unless you rev the engine for a couple seconds, even then its minimal. If its flipped upside down, then the air bubble on top prevents the water from entering because the pressure cant be released, even if the ski completely sinks underwater.
After thinking, no water will get in if it sinks right side up either, because there will be no vacuum, and air cant escape to allow water in. I dont see your logic. With the stock OEM setup with that length of tube, and the engine running as it usually is when subbing, etc. Water enters through the bulb on the handle-pole, with the suction created by the running motor, the seperator fills up, and then dumps into the tank. With no seperator, the nipple and one-way never touch water, and only when the ski sinks or flips, and even then, without a motor running to create suction, there will be no way for water to enter through that line.
No water will get in with a sunken ski and the OEM setup, because there is no suction is produced, and the one-way doesnt allow pressure out. The problem is when ski is in motion and subs and fountains and such.
