Kubota KX71-2 Hydraulic oil change

[Bryboy]

Hi guys, I'm new to this forum, been on tractor forums mostly but my faithful KX71-2 really needs a hydraulic oil change. I've owned it for 12 years and it has been brilliant, engine oil changed, regulary greased and maintained etc. but I'm stuck on how to change the hydraulic oil. I have bought an owners manual, a workshop manual (which isnt really a workshop manual) but none of them tell me how to position the boom, take the lid off the tank, drain the oil, remove the filters, clean and generally do the job and put it back together again. I have already chipped the black round filler cap on the hydraulic tank trying to open it, obviously the wrong technique.

Can anyone give me a step by step instruction on the best way to do this so I can use your experience to get it right?

Many thanks

[Muz]

Most people will have their own view on how to do it, you wont get all the old oil out as a lot will reside in the hoses, and valve gear etc. The tank will have a drain so you can empty that, you'll have to disconnect the ram hoses and rod end connecting pins and manually stroke them to empty them also, that should remove 80% of oil from the system, in practice on an older machine thats easier said than done, what with pin wear. Dont worry about air entrapment, once you start cycling rams it will all come out, but you will have to keep topping up as you go, the oil may seem milky with air bubbles at first which may make your pump sound different, but just let it settle overnight before use. Proper hydraulic aws 32 or hyspin etc wont hold air for long as its been designed not to.