I have a 84' 150 Black Max. My hyd. trim has 2 trim actuators and one lift actuator. for a little more that a year now my motor will slowly go down after I leave it in the up position. I assumed right away that I have an internal leak due to faulty o-rings in the lift actuator. but because it goes all the way down, not just down the the trim actuators I am wondering if there is something else that could be causing this such as a check valve of some sort. Has enybody had experience with this trim system? If so, any imput would be helpfull!