The power steering on my 1958 310B Gas Utility has been working fine, then last week I noticed some seepage from the outer sleeve on the power steering cylinder/valve. I cleaned, then 'bench' disassembled the valve/spool; took the valve housing & spool to the local Case dealer to match the two small o-rings that seal the valve body/cylinder and the two spool o-rings, then reassembled also replacing the rubber grommets at the end of the cylinder shaft rod. After filling & topping off the reservoir, I found that I have no power steering. I took the cover off the reservoir and using a short bolt to secure the clean filter, determined that there is good circulation. I haven't done a pressure test yet as I need to acquire a tester. Is bleeding the system to necessary? Or is there something else I may have overlooked?