RE-BUILDING HYDRO CYLINDERS

[buckrrt]

I HAVE A JD 770. I PUT THE SHIMS IN THE RELIEF VALVE TO GET MORE PRESSURE AND LIFTING CAPABILITY. SOME OF THE CYLINDERS ARE MOW LEAKING IN WHICH I EXPECTED IF THE PRESSURE WAS TO GREAT. MY QUESTION IS-- IS THERE RE-BUILD KITS THAT WILL HANDLE THE PRESSURE FROM PUTTING THE SHIMS IN, I GUESS YOU COULD SAY HI-PERFORMANC O-RINGS OR ROPE SEALS IN THE CYLINDERS--WHAT EVER IS IN THESE CYLINDERS. BASICALLY IS THERE ANYWAY I CAN KEEP THE SHIMS IN AND NOT HAVE THE CYLINDERS LEAK? HAVING THAT EXTRA LITTLE BIT OF POWER DOES MAKE A DIFFRENCE. I DIDNT GO TO EXTREME TO WHERE I AM BENDING ANYTHING LIKE THE RAM OR ANYTHING LIKE THAT. I JUST THOUGHT SOME OF YOU GUYS HAVE DONE THE VERY SAME THING THAT I HAVE DONE.ANY THOUGHTS APPRECIATED.

 

[JerryG]

If you put the shims in without checking the pressure afterward, you may develop more problems than just leaking cylinders. Just dropping shims in without checking the pressure can yield pressures in the 3000-4000 psi range. That type of pressure can damage the pump, housing, hoses, cylinders, relief valves etc as will as bend the loader frame and braces. Please get a gauge and check the pressure before you use the tractor anymore.

Welcome to TBN. (If you turn your caps off it is easier for us to read.)

 

[buckrrt]

Where do you put the pressure guage at to check the pressure?

 

[kennyd]

Where do you put the pressure guage at to check the pressure?

You plug the guage into a Quick Disconnect, like one of the ones for your loader. Then your operate the joystick to pressurize that port. Basically you are "deadheading" the system into the guage to see what the relif pressure is.

I agree with Jerry, you need to check it.

 

[JerryG]

Like Kenny said, the quick disconnects are the easiest place to hook a gauge up. If you can get a guage to check the pressure, let us know what the pressure was. If your cylinders are leaking, I would bet that it is at least 3000 PSI.