Found a leak between the fill valve and tank, which of course was at the very bottom below the rudder and elevator servos. After removing everything, replaced the tee and seemed to slow the leak considerably. However after pumping up to 100psi and operating about 2-3 times, they stop working.. I guess next is to take the entire system out and presurize it under water to see what happens. I found a place to purchase o-rings locally so may replace this new set of $135.00 Robarts with the old Rhoms. I have two other planes with retracts but they are manuel and give absoulty no problem. This is my first experience and probably my last with airs.