getting rid of the hiss
When i unscrew the cap on two out of the the three air valves on my Zodiac pro RIB, I hear a slight hiss escaping through the green plastic pins. I'd like to make the hiss stop. I say this, but I feel its important to add that once the gasket caps are sprayed with a shot of DW-40, and then screwed tight over the valves, I don't need to fill up the boat with air more than once or twice a season.
The third pin leaked air so effusively all of last summer, that I had to pump the boat at least once a week. But one day last fall, mostly out of frustration, I started twisting the pin first one way, then the other way. Suddenly, lo and behold, it stopped hissing entirely. I'm not sure which direction I twisted it.
Do these pins inside the valves actually seat themselves by getting screwed down tightly into the valve? If so, what direction do I turn it, clockwise or counterclockwise?
If my thesis about screwing down the pins to make them stop hissing is actually incorrect, I am curious how the rest of you RIB owners get your pins to stop hissing? I simply can't believe that Zodiac sells a boat with an air seal that is so faulty that there's no way to stop it from leaking, at least a little. Any advice is much appreciated.