G hydraulics?

This tractor has been sitting for ~6-7 yrs. Engine was lightly stuck :) and carb badly stuck :( that I was able to get past this weekend. I got the engine running, and after priming the system it even has oil pressure again!

My question is related to it's hydraulics. I can't seem to get them to work and wondered if anyone could shed some light on it. 1- how the levers work? and 2- any common weak points for a non-working system? I see a lever by the throttle that goes to a valve with lines to the front and back cylinders but don't know which direction is up (fwd/bkwd?). Both cylinders only have one line so I assume gravity down. There is also a lever sticking out of what I believe is the pump; am I correct assuming that back toward the engine engages the pump? (not positive as it never seems to load the engine, but think I feel it engaging gears as it goes back.) (also it's just a short lever with a hole in it, not sure if I'm missing a handle to get it closer to the operator or not?)

I checked fluid level in the rear and it was low, so brought it back up but still no cylinder operation. Does this pump need bleeding after sitting for a long time? Any other ideas?
Thanks,
Stan(VA).

ChalmersBob, That's exactly what I needed, thanks and will try it asap. I see now where you helped Don with the same question back in January, but I missed that somehow.

Don, I have the manuals (operators/Maintenance/Parts and Service). IMHO they lack detail and clarity in the hydraulics. If you are recommending them for my questions above you must have a later version than I do ;)

you all nead a service manual, big time.....