C hydraulic problems. Need advice.

Trying to get the hydraulic pump working on my C. Tractor sat outside for an undetermined amount of time with no shifter boot. Guess what the tranny and hydraulics was full of? Yep, drained, flushed and refilled last spring, but hydraulics would not work. Figured it was crudded up. Got tractor running pretty good and decided to tackle hydraulics. Pulled pump apart last weekend, it was full of crud and water as expected. Cleaned and blew out as much as I could. All springs, check balls, and seats were present and accounted for. Plungers were slightly stuck. Got both of those out, cleaned them up and their bores with some 1000 grit paper. I could not get the suction valve seats out. Manual said to use a 1/4"-28 bolt threaded into the valves to pull them out, but mine were bigger(5/16 NF?). Check balls seemed to be seating OK. Put everything back together as close to what the manual said to do as I could. Set relief valve at 9/16" like the manual said. Reinstalled everything. Started tractor and engaged PTO. Pulled up on lift lever. Nothing. Tried helping it with my hand some. It will try to raise, but you can push it back down by hand. I know the cylinder is going to need replacing, the ram is rusty and slightly pitted. I'm not even getting a lot of oil leaking by the cylinder seals. It doesn't seem to be building pressure.

I'd help, but you already tore into yours more than I have had to tear into mine.  Don't know what else to suggest.  I have a feeling many here are thinking the same thing?  But I'm sure someone has an answer for you.  Good luck.

Might be full of air. I operated it several times. Did get some oil out by the ram seals. The manual didn't say anything about priming it. Just covered testing it by hand before installing. I didn't have a pressure gauge to do that with anyway. Does anybody know if it has to be primed? If so, how?

Steve, the cams on the PTO shaft seem to be working fine. I do have the PTO engaged when trying it. I did not try taking the hose off first. I did punch the balls on the discharge valves with a brass punch. I couldn't get the suction valve seats out, that may be where the problem is. They may not be seating right. I was able to drive out the relief valve seat. I set it back to 9/16" from the machined plate where the ser# is. I think I was reading that right? I'll have to try it with the hose off, but i'm afraid i'll have to go back into the suction valves. I can feel a slight pulse of pressure on the hose when I try to lift it. Are there supposed to be any kind of o-rings on the piston plungers? there was nothing but a groove on mine.

the 9/16 dimensioin is fine as a start. after the tractor is running and pumping o.k., you put a gauge on the hose and see what the max pressure outlet is... you can take off the plug and tap the piston down further than 9/16 if you only have 2500 psi or so... dont go to far,  1/16 inch more is WAY big.... were talking  .020- .030 type movement to get more psi.

Dream, I've only been into one pump and that was for the "Build a B".After going through it all I put the pump in a vise and used a porta power with gage to "adjust" the relief valve. It took several adjustments to get good pressure out of it. I still don't know if it worked out ok cause the hydraulics haven't been used that I know of. The relief could be bypassing, it might be the first thing to check.