Can anyone out there help me figure out what to do about a hydraulic leak around a check valve on a 580L case backhoe? I had a dipper check valve spraying fluid out the top recently and I replaced the check valve and it fixed the problem. This time the hydraulic fluid is spraying out around the check valve and the block that it seats on. I thought the o-ring must be bad. So, I loosened the check valve and the o-ring is still intact. If the check valve goes bad, could fluid spray out around the o-ring without breaking it? I have already checked online for the replacement part and can only find it 1 place ---from dealership for around $800.00 ! The dipper check valve was around $80.00 ---BIG DIFFERENCE !! The part # is G109627 ,It is # 3 in the picture. {the left outrigger if seated facing boom}It is the valve at rear of outrigger block-not the one that attaches to the outrigger stick . ..In the picture it is beside #2 .Number 2 has been repaired and no longer leaks.
Are you sure it's leaking at the relief valve and not between the sections? If you are sure that the leak is at the valve I'd check for a crack in the thread area of the valve section. Another question; Is relief valve leaking at bottom of valve or top of valve?
I am sure. Sitting on machine digging ,I could see a steady spray coming from where the threads would be, between the valve and the top of block. Thats what made me sure the o-ring had blown. But it didnt. I will check the threads when it gets a little cooler. I had to get inside and cool down. Pretty hot here today! Thanks
I understand about heat stay cool down there and drink lots of water. One other thing you could do is swap check valves to see if problem stays in that section or moves with relief valve.
I will take your advise. One more thing ,if you dont mind? I have removed the other valves that linkage is attached to and know that you remove bottom caps ,and then they come out bottom. also ,that they are spring loaded. I wasnt expecting this particular one to be spring loaded, but it is. Question is, ---What is best way to get it back together ,since the controls are all in a tight spot between joysticks and floor of machine? On other, I used small hydraulic jack to exert small pressure upward until I got cap threaded. Will this one also unscrew from bottom?
The spring should be attached to the spool. I’m assuming you are talking about the stab. spools.
Dont know what its called. Think probably the spool. When I screw the check valve off ,the spool was under spring pressure ,and came out . So, I will have trouble in such a tight spot getting it threaded back in since i will have to press it down enough to get check valve screw back in. I probably need to pull up a schematic in order to see what all is in there. just having trouble finding a good one. Thanks!
Oh ok that is the lock check poppet spring for the stabilizer, it prevents the stabilizers from letting the machine leaking down when it's lifted up in the air.
Coy ,or anyone else that might know, I pulled up schematic of the stabilizer control section and can NOT see any sort of spring that would be at bottom of spool .But it was under pressure when I took it out. Do you know if there is a spring below the spool at #14 ?? The leak was at 16 and top of block section when 16 is fully seated on block. Thanks, Larry
There is none on the bottom. But there is one on the top--#23. Sometimes those little springs are missing after someone takes a spool apart and don't see those little buggers going flying.
Hey , Thanks! I didnt take 16 apart, so I should be good on the springs Must have been under fluid pressure? Thats good to know for reassembly.