The valve that works my loader also runs the 3 point hitch. It's leaking hydraulic fluid and I can't read the brand or part number. Northern Tool has some valves but I'm not sure if any of them would work, does someone know?
Might want to ask over in the New Holland (which also includes Ford) section (link). There is a lot of good 1700 info/help there. Pictures of your setup would be helpful as well.