2590 hydraulics and powershift

I am at the end of my rope with this thing , changed both pumps , cleaned screen numerous times and don't seem to find a lot of stuff on screen but tractor will run a few minutes and then all hydraulics quit, Ive tried to rent hydraulic testing gauges and none are to be rented or used , so I broke down the tractor thinking maybe the gears in the pump drives might be bad, but they look good , anyway I found this on the powershift unit the clutch plates with the tab look bent , is something wrong here because it doesn't look right
And thanks for any responses Randy

have you torn apart the compensator valve I know it seems looney but 80% of my hydraulic trouble is there.

That has also been replaced with a rebuild one that was with the pump , thank you

Its hard for me to tell from the picture whats wrong. But have you ever checked your charge pump?

https://messicks.com/cas/68221

If a key is sheared on a gear that could cause your trouble.

Yes there's something wrong in the ps , but that's not causing the hyd problem, does the tractor still move or do you lose everything? If you loose it all need to check the charge pump deals and shaft key

No use tearing it apart until verifying what the oil pressures are . Odds are there is a leak in the low pressure oil system .

I have not followed this forum very well as of late so don't know what you have all checked. Forgive me if this has been asked, just wondering if you have good charge-pump pressure after the main hydraulics quit. Rod.

Thanks for the reply's , yes I changed the charge pump, was last thing I did before tearing it down , the seals look good on the charge pump and the key on the shaft seems alright, I have a makeshift pressure gauge rigged up on tube from charge pump to main pump and it shows 30psi when I start the tractor but I didn't let the tractor run very long because there was no oil running to the main pump because the tube is blocked off with pressure gauge , there is a fair amount of damage to the gear that hold the park stop from it apparently being on ,I noticed that a while back and took a lot of iron filings off the screen when I flushed it previously I must have flushed the screen 5 times and it doesn't look that bad ,I have called everyone I could think off to see about renting a testing kit to check pressures and no one will rent them out , so anyway I have a couple days and thought I am fixing this thing and tore it apart and it looks like the tabs on the clutch pads are bent in the picture, what would cause that ? . Anyway I really appreciate this site and not its time to teardown the powershift pack , thanks again

Excessive heat and or pressure would warp or bend the tabs. The bad part is we dont have the normal diagnostic information that a pressure test would have given us.

Since you are apart I suggest you go ahead and pull the power-shift clutch apart that you have in the picture and check the seal, replace if needed and replace the plates for that clutch.


But i would like to help you work this problem out. Maybe Rod1370 could chime in and help figure some of your problems.

Did the brakes work before you tore it down?
Did the hydraulics work before you tore it down?

I know you said you have cleaned the screen several times but minute particles in the oil will plug off the screen. I once worked on a Power-shift that had strong pressure at the charge pump but has you speed the tractor up the particle matter from a clutch failure would come off the walls of the rear end and plug the screen.

The only way i got that taken care of was by pulling the rear cover off the tractor and washing it out with diesel.

More than likely you have a clutch plate or pressure plate failure. It could be from the clutches, the brakes and even the PTO and Differential lock plates.

Since you are already apart you might as well go ahead and start checking everything through a process of elimination.

You mentioned that all hyd's go away after running a short while. I just want to confirm that the filter pressure or charge pressure is the same when the systems is operating properly and when it is not. You can remove the pressure sender and install a gauge right in the line and monitor it. Rod.

The brakes and steering worked for a few minutes just like the powershift then would quit, actually it felt like there might have been a very little hid pressure as it might steer very slowly and it would move also in low low very slowly enough to get it into the shed, thanks for the reply Randy