Yamaha tilt and trim relief screw

My 2012 175 HPDI tilt and trim relief screw loosened while on the water. I put the boat on the trailer and tightened it. Put the boat back in. It didn’t have the power to raise under power. I found a seal leaking. I replaced both trim pistons. I still have the same problem. It seems to be full of fluid. After bleeding air it seems to work ok but after sitting for awhile to problem reappears. I have repeated the bleeding process 3 times. Same result.

I would ay got water in pump nd need to get it rebuilt and flushed out