Hello everyone, this is my first post My JD410 backhoe has lost all hydraulic power forward and reverse movement works. I have no power steering or front or rear hydraulics. I have changed my 2 filters and cleaned the screen that goes in horizontally into the tranny case, the screen had some metal filing. I do not believe the screen was ever serviced before. I have also removed the front hydraulic pump and replaced the input shaft and coupling as it was showing wear. I still have no hydraulics. I have replaced the electric solenoid on the side of the main hydraulic pump and it made no difference. Intermittedly i will have a slight amount of hydraulic flow but it will only life the rear jack pads about halfway up and very slowly. i have removed the front pump again and the hydraulic pump rebuilder said there is nothing wrong with it. please advise, any help is much appreciated.
Check the hydraulic filter head on the left side of the transmission, there's a spool valve in there that opens and dumps charge oil back to the trans case when pressure exceeds the set pressure. If it's stuck open the hydraulic pump won't have enough inlet pressure to create flow.
No personal experince to help, but I have a set of manuals for sale if you need them. [email protected]