I'm working on a 500c john deere backhoe and I did an hydraulic filter change and found what I guess is sludgeto the touch it like silicone and when squezeed lookes like a redish brown with a light fiber theres nothing hard by any means so the machine travels fine and the front loader and backhoe move but can lift them selves and nothing else so could it be the screen holding back the flow it whent from powerful to how it is now in like 15 mins i changed the filters and put in new tractor fluid but I couldnt find the screen Im pretty sure wheres it is but Im afraid I weill have to drain the oil all out againI also read theres a trany pump that hes to reach a certain pressure to kick in the front pump ? could the screen hinder that?
Welcome to HEF Leroy ! Assuming you have a powershift transmission? I would definitely check that screen. Unfortunately you will have to drain the oil. It will be behind a plug on the bottom of the transmission that has a manifold (#29) on the opposite side.
Thank you you just confirmed what I was hopping to get out of draining the oil this all started when a main hose broke and it goes on the right side of the pump but a fitting that was soldered was tweeked and leaked and the machine had to be moved and I couldnt get the new hose back on cause the frame was in the way so I put the hose on the top of the pump which worked ok for about an hour then everything went week so I changed the filters and found the what I believe to be sludge no metal nothing hard in the oil at all!! so Im thinking screen but the I heard about the trany priority valve so with the screen almost plugged would that constrict the flow where I can still lift the front loader up enpty and the hoe but with no power
Another item that could affect your loader and not the transmission would be the priority valve. And if you have sludge in the filter, then maybe there is sludge in the spool or its orifice. If the screen or the priority spool are not the issue, then a more thorough diagnostics will need to be performed.