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Hydraulic oil change

troyharnish ยท 2011-12-01 17:50

I want to change the hydraulic fluid and filter on my 2002 Case 580 M turbo, Just wondering if I could field a couple questions before I do it. I have enough mechanical know-how to change fluids and such, not much more, but I do like to change my own fluids to make sure they are done at the proper intervals. * How tightly should the new hydraulic filter be screwed on? Similar to a regular oil filter (i.e.- hand snug then another quarter turn)? * Can I use a regular filter wrench to change the hydraulic filter? * In order to drain the hydraulic fluid from the tank, it looks like the plug has a large hex in it, what do I need to take the plug out? Any guidance is appreciated.

Replies9
  1. #1bowen2011-12-01 22:16

    View attachment Hyd Fluid.pdf See if you can see this. This is out of the manual for a 580SE but I suspect yours is similar. You can change the filter without changing the 12 gallons or whatever yours holds. It is similar to a car just bigger, and can be a bit nasty: getting oil on the engine. Next time I will be better prepared with rags under the old filter.

  2. #2troyharnish2011-12-02 13:26

    I was able to see the pdf, with thanks. I have located my filter under the machine, in front of the rear axle next to the driveshaft, and I have the correct replacement hydraulic filter. I want to change the hydraulic fluid at the same time, because I have no idea when the previous owner did it last. I think the owners manual says that there is a special process to follow after you drain/ change the hydraulic fluid, to prime the system. Anyone know if I need to do this if I just empty the tank and refill it? If so, how do I do it?

  3. #3alrman2011-12-02 16:46

    1) Correct - hand tight + 1/4 turn. 2) Depends what you call a regular wrench....... Most good name wrenches will work - but I have found some super tight ones, usually on newer machines when the factory fitted one has to come off, or maybe a gorilla fitted it last time - You won't know till you try. 3) Drain plug is usually a 1/2" allen key..... from memory 4) Make sure that if you ever try to remove a filter, before/without draining the oil , relieve the air pressure in the tank. 5) Usually it is a drain & fill job....... usually....... with the L & M hyd tank configeration, sometimes, not always, they wont pump oil after an oil change. To prime, with the engine idling, you have to loosen the pressure hose - the closer to the pump the better. Sometimes, with engine idling you can use compressed air to pressurize the hyd tank - to push some oil through. :drinkup

  4. #4troyharnish2011-12-02 17:08

    Perfect! I think I am ready to change it, now. Thanks for the priming info, it sounds like it is just a vapour lock type issue.

  5. #5inthedirt2011-12-03 17:26

    This has already been said, but I just wanted to make sure you understand! We have had several customers change their hydraulic oil and not prime the pump and in the time it takes to start the engine, say, "oh crap!" and shut the engine off, they burnt up the hydraulic pump. Since the tank is lower than the pump, you MUST get a head of oil to the pump before starting! Some guys will keep the boom in the transport position and run the dipper all the way out (up in the air) have the loader up in the air and after putting oil in the tank and put the cap on the tank will lower the dipper and loader so that they are pushing oil in to the tank causing air pressure to build. My personal favorite way is to use a tank cap that we gutted the spring off of and brazed on a JIC fitting and then hook 10 psi of regulated shop air to it so there is constant air pressure on the tank. then unhook the shutoff wire and crank the engine while pulling back on the loader handle. It will take just a few seconds and the loader will start to raise (and load up the starter) and you KNOW there is a good head of oil at the pump. If you don't have the cap setup, you can get a buddy to wad some rags around a blowgun and put in the neck to put air in the tank. just don't put more than about 10 psi in the tank cause it doesn't do anything good for the breather.

  6. #6troyharnish2011-12-04 07:27

    Holy crap, that's good to know. I didn't realize I could fry the hydraulic pump that quick! I don't have a way to easily pressurize the tank with air, so I am going to use the extend the dipper and bucket trick, and perhaps as an extra safety, I will disconnect the shutoff wire and crank the engine while pulling back on the loader lever, to make sure the system is primed.

  7. #7alrman2011-12-04 07:46

    I have carried out the proceedure described above on maybe 2 or 3 machines out of dozens that I have changed the oil & had no hydraulics - at an idle you will know straight away if you have a problem. Shut the machine off, make preparations & prime it. Never damaged a pump. Chances are you wont even have a problem. When guys say they fried their pump in seconds - they don't tell the full story, like they actually reved the c&@p out of the machine for half an hour trying to get the thing to go.......

  8. #8willie592011-12-04 10:16

    Ditto. :iagree

  9. #9GManBart2014-12-22 08:22

    Rather that starting a new thread, I thought I would revive this one. I'm planning to change the hydraulic fluid and filter on my new to me 580 Super M, so this is helpful, but I have two questions. 1. I'm considering changing just the filter now, and doing a full fluid/filter change in the Spring. The dealer said the fluid was good, but they didn't have records of when it was last changed. If I change just the filter now (sort of like how Case recommends changing just the filter after 100 hours) do I have to worry about recharging the pump? I'm guessing I won't put more than 50-100 hours on it over the winter, so it's not going to be a lot of time until I change the fluid. 2. The manual says it holds something like 32 gallons, but a change only requires around 14 gallons. Is that simply because the lines and cylinders hold the other 18 gallons, or are they including the transmission sump as well, or something else?