Can't wrap my head around this one so was hoping someone else with a bit more familiarity might be able to shed some light. Recently replaced the motor and piston seals on the T&T for my old V-4 Crossflow. Did NOT do a complete overhaul b/c didn't think anything else was wrong with the system. Now, when I fill with fluid per manual recommendations, the twin small cyliders extend and retract as they should, but the primary cylinder actually extends only when the switch/motor are running in the "Down" direction. once the main piston is extended, it doesn't retract unless I open the manual release valve, and even then I can only press it back part way before it starts to get springy from compressing the air bubbles in the now frothy hydraulic fluid. Can't figure out for the life of me why the main piston would extend while the other two are retracting though. 
It's like the hydraulic fluid is going in wrong direction for just that one piston. Perhaps the air bubbles? I've drained and carefully refilled the unit three separate times now but no change in result. Perhaps a stuck internal valve? Would really like to get this thing working so I can replace the old rusty one on my boat with cracked/leaking seals before my company comes this weekend. Any ideas guys?
It's like the hydraulic fluid is going in wrong direction for just that one piston. Perhaps the air bubbles? I've drained and carefully refilled the unit three separate times now but no change in result. Perhaps a stuck internal valve? Would really like to get this thing working so I can replace the old rusty one on my boat with cracked/leaking seals before my company comes this weekend. Any ideas guys?