On the bottom the the trencher there is a dozer blade and there is 2 little cylinders to tilt the blade. Today I rebuilt both cylinders because one leaked really bad and one didnt work right. The one that isnt working right is getting pressure to both sides on the cylinder when I run the valve. Does this mean my spool valve is junk?
your rig probably has a regenerative circuit on the hydraulics. This puts a back pressure on the retracting side of the piston to keep it from cavitating and getting a jerky air pocket in it. Where your main functuion is 2500 psi your regenerative side will have 200 to 500 psi. Dad got nice JD loader tractor at a sale cheap because the hoses were hooked up wrong it still worked right with the joystick dumping if you barely pushed the lever right it still dumped but if pushed it all the right and quick ly it would dump then curl I told dad about it we switched the lines back and its still working great.
That may be part of the problem but today I tore the machine apart and the one of the cylinders I rebuilt was missing some of the seals and I think I found where those seals went. One hose is packed full of something.
I think what you will find is that the cylinder is bypassing. There are 2 things you can do to identify a possible cylinder bypassing. Carry out a cylinder bypass test or after operating the machine take the tempratures of each blade tilt cylinder - the one bypassing will stick out like a sore thumb with the temprature being considerably higher.