last weekend i hit an unmarked buoy at night going about 35. I started having problems with the drive going down. limped it in and took apart the trim motor. In the resovoir I found the in/down pressure relief valve body, the spring, retainer and ball. I put it back together the way it was supposed to go but I have no pressure at the pump on the down side. Do I need a new pump, relief valve, check valve or what?

So you've popped the valve out and re-assembled on the in/down side? Did you check the up/ out side? The relief valve that allows pop up if you hit an obstruction rarely (one would hope) gets used so it gets sticky. The in / down valve from memory serves to stop your drive falling down while in trailer or tilt up position. Check the other fluid circuit. I had a similar experience on a friends boat recently, we had to trim all the way up and hold to relieve pressure in the circuit and then I put pressure on the drive while trimming down to pop the valve back in place. If you hear the pump running, it's all good. If you hear the soldenoids click, that's the pressure circuit, if nothing happens, check the elec / soldenoids by jumping for direct feed.

If your check valve is stuck, you'll hear a high pitch whine like there's no fluid ('cause there isn't).

Good luck!

thank you for your time. I completely disassembled the trim motor and pump and found that the motor to pump coupling was in two pieces that were broke on a diagonal line that let the pump work in the up but pushed itself apart when in down I welded piece for this weekend and am in the process of ordering a used one from a junk boat dealer. again thank you for taking the time to answer my question.