Hydraulic Problems

I lost all hydraulic functions on my 30 yr old L245DT (loader and 3PT). Checked fluid OK, cleaned filter OK, checked relief OK, I do not have access to a pressure gauge but with cracking the pressure line on the pump there did not seem to be much pressure with the tractor running. Removed pump and disassembled, O-rings fine, some wear on gear face and inside of pump housing but not excessive. Purchased new pump and installed but no change. When tractor sits overnight and when started the 3PT will raise, then will only lower and not come back up. Removed pressure and return lines from loader control valve and connected together and still no 3PT function. I am assuming there is something wrong with the 3PT valve inside of tractor case which is taking all the hydraulic pressure. Can anybody help point me in the right direction.