I went back and read my original post and it was not really very clear on the problem I am having. I'm a small farmer that works, for the most part, alone. I need to pick up a light duty backhoe to help ease the workload. I found this 530CK in very nice condition overall and at a price I can afford. It is old...but not abused. The ONLY problem it has that concerns me is with the boom cylinder hydraulics. For example, if I place the dipstick so that it is pretty much vertical and extend the boom cylinder, the machine will lift off the ground. However, as soon as the control lever is released, the machine drops down a couple inches. All of the other functions are normal. Does anyone have an idea what could cause this? And, importantly, is this a "deal killer" problem?
Any of the three things you mentioned in your other post would cause this. I don't think there is any other possible cause. The "lazy relief valve" may or may not apply to this machine, I don't know. Either the cylinder piston seals are leaking (internal), or the valve is leaking (also internal). To me the piston seals are easy to fix if you can get the cylinder apart yourself, or not that expensive if you can get the cylinder to a good shop. A cracked valve body would be hard to remove and hard to find a good replacement. The cylinder is the more likely problem. It's up to you if this is a deal killer. If it's clean with good tires, it may be a deal. You may start using the machine and realize that you really don't notice the leaking down pressure when digging. How bad does it leak the other way? if you extend the bucket as far as it will reach horizontally, how fast does it drop to the ground?
Thanks for responding - I appreciate it. I'm going to go "test" it again today and answer your question. I'll extend the boom and see how quickly it drops. Can you tell me what it means if it stays up? Or, what it means if the boom drops? I do not see a leak in the valve body on the outside. It is clean and dry. The boom cylinder on the model 32 BH is inside the boom. I learned that on the model 33 they moved it to outside the boom but the booms are otherwise identical. This is a 3500 hour, one-owner machine that has not been mistreated. One rear tire needs replacing. Minor seepage from a couple cylinders and lines, nothing to get excited about. He is firm at $5500.
If the cylinder holds the boom up, but won't hold the machine up, then at least the barrel of the cylinder is in good shape and most likely the piston seal is fine too. More likely the valve or relief. If the boom drops about the same rate as the machine settles back to the ground (considering the weight), then it's probably just the worn piston seals. If you can, fill the backhoe bucket and see how it settles. The boom dropping enough to notice while you're digging would be a problem that you'd want to fix.
One other question...if the valve body is NOT cracked, could there be an internal problem that is major, as in "need new valve body" major, or would it likely just need a rebuild? My real concern here is that some years ago the owner rebuilt the valve body. I'm wondering if it would need it again and if that is reasonable for the 3500 hours that are on the machine. All other control functions seem fine. Those hours look legitimate to me...this machine is not worn down like you see with a 10k hour machine. BTW, I really appreciate that you took the time to think on this and answer. I'm pretty ignorant about hydraulics but one thing I do know...5500 bucks is a lot of money to my family. I don't want to screw up because I didn't do my homework.
I'm not familiar with Cases, much less this model, but in general hydraulic valves leak that leak internally are cracked or worn out, neither of which is practical to fix. The seals that get replaced are only the external seals, internal is metal to metal. 3,500 hours is irrelevant to hydraulics, 50 years and who knows what else is the real issue. Cracking is an issue on specific models, not sure how widespread? Worst case, you spend a lot of time scrounging a used one that will work. Unsolicited point of view: 5 grand is a lot of money for a 50 year old backhoe, construction equipment doesn't hold it's value like farm tractors do. If you have time, you should be able to find a 25 year old Case or Deere for that kind of money, but it won't be pretty. If you want to do a lot of work, then the "middle age" machine is the way to go, on the other hand if you're talking about just doing your own building projects this antique may be exactly what you need, slow and simple. You could always wait until the owner dies, but then it might go for a lot more at auction?
LOL, yeah, I could wait...but I decided not to. I just bought the thing about half an hour ago. I went back and tried it out again and did the tests you suggested. The boom does not sag when extended horizontally and parallel to the ground. Stretched out like that, it just hangs and does not leak down. The bucket, filled with dirt, does not sag or "drift" either. BUT, I noticed that when I picked the machine up with the boom and let off, the "squeak" sound it made when the pressure dropped was coming from the cylinder inside the boom. This is the one I'd call the boom or lift cylinder. It is very distinctive. When I was listening closely, it is clearly coming from the cylinder and not the control valve or the relief valve (or poppet or whatever its called). I suspect a rebuild of that cylinder will take care of the problem...and, frankly, I probably wont bother doing even that until it seems truly necessary. I know that there is probably a nice 310 out there somewhere in decent shape for the same money but, so far, nothing I've seen is nearly in as good condition as this old hoe. There are no welds, the pins and bushings are in nice shape, the engine purrs, and the cylinders are mostly pretty "shiny" and free of pitting. It has both a 12" and 24" bucket, too. Honestly, I think I can put this hoe to work as soon as I get it home and it won't truly require a thing. For my needs, it'll do. And, a 310 weighs about anywhere from two to four tons more than this little 530ck. That extra weight might be hard on my asphalt driveways...I have 1500 feet of driveway that loops through my place and don't want to pressure it more than necessary. All in all, this seems like a simple "farmer's" machine. All in all, I'm OK with the old girl. We'll see if I'm still happy in a year or two!!
Del, one other question: Do you really see decent machines for $5k?? Every machine around here (the Thumb of Michigan) that I've seen on CL for $5k was pretty ragged out. Most every machine I've seen under $10k has problems like blow-by, welded up booms, slapped out bushings, won't shift into high range, etc. Honestly, I have not seen a think in that $5k to $8k range that I liked...and when you listen to the owner's story, the stories sound "off"...like "I'm only selling because I have to buy a new car" when what they really mean is "This pig is bleeding me to death". I liked this one because the bushings were good and the machine showed no signs of heavy repair. The owner was the only guy that ran it since he bought it with 300 hours on it in 1975. I figured that alone was worth an extra grand!
Hey now, I never said DECENT. I agree, clean and running right is worth a lot. A $5,000 dollar backhoe can turn bad fast. I have seen decent backhoes listed in the $4-8k range, but not in person, so it's hard to say what they really were. As for the cylinder squeak, any chance it's the pin making the noise? You could look up a diagram of the cylinder to see what kind of seals it has, or maybe somebody knows if those cylinders will leak in one direction and squeak. Also, you mentioned the rods are "mostly" free of pitting, if there is any rust or pitting, you want to sand the edges down smooth so the sharp edge is tears the seals up less quickly. Just take some 320 or 400 sandpaper and smooth it out. Good luck and enjoy!
Thanks, Del. What I meant by "mostly" is they aren't shiny chrome like new rods, but neither are they rusty or scappy looking. When I get the thing home next week I'll snap some photos and post. I do plan get after the cylinder rods. What little "pitting" is there is very minor...just enough to mess up new seals a lot faster than they should. I plant to go over them carefully and clean up anything I find. There is a little seepage of oil but, really, nothing to get excited about. One buddy of mine said "just start using it...some of the little problems will go away with use" and I kind of think he's right. Nothing is worse for hydraulics, I'm told, than to just sit there unused. I talked to a Case guy - the parts man at the local construction equipment dealer. He was a mechanic for 15 years before moving to the parts desk. He told me rebuilding the cylinder was "doable" for an amateure and not terribly expensive even if I took it into them. He also mentioned that what causes the "squeak" is the oil sneaking by one side of the seal. His explanation sounded knowledgeable...but I forgot a good part of the detail. I suppose I'll remember better after writing the check to fix it!
Oh year, one other thing: The squeak is distinctly the sound of oil squirting past soemthing...like squirting through a hole. It isn't a metal on metal sound, it sounds like when you let the air out of a balloon to squeal it. Here's a pic of the hoe that the owner posted on CL.