8n Hydraulics INOP

So working on the old tractor again. My dad told me the hydraulics didn't work at all so I pulled the side cover off the transmission. Basically regardless of where the lift lever is positioned this is the behavor I'm seeing in there. Granted there is alot of water in the oil but based on what I think I'm seeing something is stuck on the pump IE the relief valve or something along those lines.

I already know the top half needs completely gone through being when the hydraulics did work it leaked down super fast. That and the draft control system hasn't worked properly since I can remember.

https://youtu.be/TKzA5qgfGzo

Does the control rod from the lift cover move the control valve in the pump...

Someone is gonna say first change the oil its too late for that even if it has water in it the pump will pump it and the lift should work... The water may be the root cause if nothing is stuck it should still function...

It would have been nice to drain it before you ran it the water would be in the very bottom and came out first : ) now you have mixed it even tho you are headed that way diagnose it before you waist money on new fluid...

So far to me its looks somewhat normal make sure the pump controls are working... Put your hand down in the oil does the control valve in the pump move when you move the quadrant you do this with the engine OFF... Are you can drain the oil and look thru the drain plug hole for control valve operation...

If the control valve is stuck you can feel the resistance in the quadrant if you are lucky you can break the control valve loose with a long pry bar thru the inspection hole prying again the control rod from the top of the lift cover... Yes you can break it : (...

Where the control linkage fits the controls on the pump, drain hole below it where you can see it function and pry on it to un-stick it if its stuck...

Mr. Hobo listed a few good places to start -control rod not inserted into the pump base port? Bent or stuck control rod? And, yes, water in the system isn't good but lift should still work somewhat. Did you perform the lift test? Attach an implement and raise fully up or raise lift and chain down the arms. Shut down engine leaving in raised position. Look up thru the inspection cover ports to the hydraulic cylinder with a flashlight. Watch closely to see if hydraulic oil is seeping out down around the piston and wiper seal. Yes? Problem #1 identified. Top cover needs to be pulled off and cylinder & piston replaced with new. Pump and chambers can be cleaned without removing pump base, but depending on how much gunk is in there, or if the pump is cracked from water freezing and then activating pump, will need to be dropped and rebuilt or replaced o cracked. A rebuild will include a new safety Relief Valve but that isn't your problem now. Define root cause. Fix. Get the proper manuals and documents for a reference guide and do it right the first time. The top cover is heavy so get help. Do not take shortcuts. Thinking you can just hone or rebore the cylinder is a mistake -GET NEW. Use the NAA-530-B Piston with rubber O-RING -they will work better than the old 3-ring piston. The 8N cylinder housing has a cast or machined scallop at the 7 O'Clock position from the port face to clear the control rod mechanism. Most reliable part suppliers sell complete gasket kits, pistons and seal, and cylinders. Check cylinder for scallop. If it isn't there find one that is. Contact me for my 8N Hydraulic repair article.

Tim Daley(MI)

More than likely this is what his is gonna look like...