Hi all, my name is Matthew. Not sure if we are supposed to give a more formal into/background, but I'm 18 and a self taught machinist that's trying to start a heavy machine shop with a bunch of junk. Yesterday Dad and I took delivery of a Case 1285 wheeled excavator. I took a video of unloading the machine; https://www.youtube.com/watch?v=I_fdFDXMjbs Head phone users beware, you have to yell to be heard over the engine and since I was holding the phone in my hand when recording, I was basically yelling into the microphone.... What I know is wrong; one tire went flat and sat down on the rim somehow damaging it doesn't hold air for very long (split rim style), the throttle has been disconnected because it's stuck in the wide open position, no brake and the fuel system hard lines leak so it sucks air and eventually loses prime after sitting. I also think that the air pump is not operational, simply because the systemic failure off all systems using air in someway. And I also think that the brakes have been disabled somehow, with a lack of air, they should lock in place but there are no brakes. But I don't know if those assumptions are true yet. The problem was that when it was parked yesterday, we shut it down and then tried to fire it up again to see if the prime was still good. But since I was in a hurry when I put some hot batteries in it to get it off the trailer, and the 1/2 nuts on the terminals were partially rounded. All I got was a big spark when I attempted to start the machine and a slightly melted battery post (it's 24v). Well Dad and I were working on it again this afternoon, changing fluids and filters, cleaned the battery terminals and posts. Went to start the machine, and got nothing. Not a single sound, movement, nothing. I started to probe around with a voltmeter and everywhere I test shows current. So could that spark have fried something? If so what? This thing is pretty darn complicated, could it just be electrically interlocked out? Also this is really going to sound like a stupid question, but I can't find the starting solenoid. We have a Case W-11 that the key switch is bad and we start it by shorting across with solenoid with a wire. I was thinking that would bypass any possible interlocks, but I can't even find it. I'd appreciate any info ya'll may have about this machine. We bought it to do dirt work for a building I'm going to build to get my machine tools out of the weather and to overhaul Dad's junk farm equipment. I apologize if this is sounds like a basic problem, it's just this is the largest and most complicated machine I or my Dad have ever worked on. I ordered a parts and service manual last week, but it turned out to be water damaged beyond uses. I've ordered another, I'm waiting for it to come in the mail. This has the Case 504 engine and not the Detroit 4-71 like some do.
Bit of a bump/update. Been working on the machine and thought I had all the problems solved on it. The leaking hard lines and losing prime was solved by installing one of those little electric pumps in the fuel line. The throttle, that's being run right now with a string, will eventually have a hand throttle replacing it. The brakes are really confusing and a big mess, so what were going to do it route a brake line from one of the master cylinders (it's got two main brake master cylinders), to the brake. We'll only have 50% stopping power, but that will work for us. But now the problem is that the swing control has stopped working. We shut it down for lunch, came back, everything worked except the swing. First think I'm going to check is the house brake, but I don't think it's that. I'm hope it's something simple and that we need a new drive motor or something..... This old girls got no factory support..... All in all, I can see why trackhoes are much more popular. These are very cumbersome to drive (it's pretty bad when a 25k yard forklift handles better), are loud, rough, slow, very complicated and will be very expensive to maintain. They are this way because of the design of having a house mounted to a chassis. Would have been much better to move the engine behind the operator. That would cut down on the complexity because then you wouldn't need any air/electrical controls to go through the turn table. And to control the wheels installing hydro-static drive motors to each wheel would have been much more efficient then the cluster for a drive train it's got right now. Attached are the pictures of what it was doing before the swing control quit.
It's old Drott technology, you get what you get. Gotta expect lots of issues, these things were high maintenance when new. Wait for the manual, go through one system at a time and make that one work properly. The shotgun approach to try and get a job done may end up getting someone hurt seriously. Good luck with her.
Hi lantraxco, "You get what you got", that's a very euphemistic way explaining the machine. It definitely will be high maintenance, and I can easily understand why not many people (if any) like these machines. But it's been my assessment that the machine is in fundamentally ok shape (and I've been around some real junk), and that the previous owner neglected it, and all the little maintenance issues grew and snow balled to the point where it is now. As much as I would have liked a trackhoe and how a trackhoe would have been so much a better machine in almost every way, the cost of a trackhoe was prohibitive. So that means I've got to get this old POS to limp along and do what I need it to do. I've got the manual and have been going through it, but so farm of the problems have been leaking lines, and bad wires. I'm hoping the swing problem will be just as simple, but according to the manual it's a simple bi-directional hydraulic system, so I'm afraid it's going to be either the swing motor, or the brake being locked up. I'll know more when I start to tear into it this week. A bit off topic here, this isn't the only big project machine I've taken on, I just got done with a Hyster H250H. It needed the main cylinder repacked, steering cylinder repacked, new tires and a few other minor issues. But once I got that done, it's now worth about three times what I paid for it and that's still cheap for a forklift of that size. I don't think this machine will ever be that good a deal (be glad to sell if for what I bought it for), but if it does what I need it to do (dirt work for building and hang trusses), it's well worth it. The picture is the Hyster lifting a 15,180lb Kearney and Trecker 5CK milling machine.
The wonderful thing about old Hysters is that once you fix one, you will probably outlive the fix, lol.
It's a pretty nice machine, not much to go wrong with it really. But after running this one for a while, I'd really like a bigger one. This week in addition to losing the swing control, I also lost the crowd control. Tracked the linkages, the only place where these two controls are connected is at the control valve/spool value. There are two of these valve assemblies, one with three controls and one with two. The one with two is where the swing and crowd controls are located. A bit of logic says that since the two controls failed (almost simultaneously) and everything else seems to work, that the problem is the spool values. Have never torn into a spool valve, so I called the heavy equipment mechanic I know. He's a bit of a strange guy, he doesn't turn any wrenches, he just tells me what to do. It works great for me, I learn how to fix what ever is broken and the guy is really cheap. But he couldn't come out all this week, and will now be gone for two weeks. So I will either have to call another (more expensive) mechanic out, which has it's benefits, or figure out how to fix it myself. So has any one reading this ever worked on a spool/relief valve assembly? I think the hardest part about fixing it would be getting to it. The smaller valve body is located under all the lines for the other valve, I think I would have to disconnect the larger to get to the smaller, not looking forward to that. The machine was also 20 gal low on hydraulic oil Amazing it did anything at all with the oil that low.
Are the spools moving in and out properly, and both centering correctly?
From what I can tell, yes. They appear to be moving what the book says (3/8") and going back to center. The book mentioned O-rings in the spools, could it be that?
Check valves, O-rings, main relief stuck open.... if both problems happened at the same time I would say pump problem but?
Well the hoist function works, so I don't think pump. Anything is possible I guess, but I hope not. What would be the best way to start to narrow it down? Pull the valve body and take a look? Can any checks be done in-situ? It's going to be a bit of a PITA to get undone.
If you can turn the relief out of the control valve without removing the control from the machine I would do that first. I recently had one that got a piece of rubber in it from a pressure hose that was failing inside holding it in relief. Once I got it out it was a five minute fix.
Isn't the hoist function on the other valve? That's the impression I got from what you wrote...... Usually there's two pump flows on an excavator so you get better control of the functions without having to feather the valves together as much. I have no idea on that unit though what it has for pumps.
Ahh ok now I understand. Yeah the are on sepeate valves, I didn't realize there might be two pumps. I'll look at hydruali diagram and see if that's the case.
I looked at the service manual and it shows only one hydraulic pump. I'm afraid I'm just going to have to call out someone. Its proboly a very simple fix, but I've never done it before and can see myself easily screwing it up.
I believe case pulled the 1285 from the online parts page do to Badger selling the crus-air and building the 1085c. I think some of the older drott parts now come from them also. Your pump has two sections rated at 41gpm each at full rpm. I would swap the main relief valve from the side that is not working and install it in the other valve, take the relief from there and install in the valve you had your problem with. Both valves reliefs are set at 3000psi. If you have a parts book you should be able to check the numbers. If the issue stays the same them you may have a power beyond plug issue also if the machine has a single or double auxiliary valve also installed. You should pick up a quick connect/hose/5000psi gauge with a min 10' length so you can test some pressures, on some areas you may need two hose setups for testing (in the power sensing) I seem to recall. You may also need to have a flow rater hooked up to check your pump or a shop that has equipment to flow/ inspect off the machine. I would switch relief valves first if they are the same and check.
After some testing with a gauge, found that one pump was putting out 30PSI and the other seemed to be OK. Both are now sitting on the bench waiting for me to figure out what to do next. Found the placard on it for model/part number, all that info is gone. The only thing that's there is S619344, both pumps have that number. Any ideas? Just let a rebuild shop lose with it?
Probably should have swapped the pressure lines, if they were long enough, and checked again. It's more likely a valve issue than a sudden pump failure, but you never know. Pumps create flow, resistance to flow creates pressure. Either the pump is not creating flow, or somewhere within the pump or the valves downstream, there is a large enough internal leak to lose the resistance to flow back to tank, and therefore the pressure.
The way the lines were run, swapping them would have been impossible. The pump was easy to take out, it would be fairly easy to put back in. The gauge the mechanic's had turned out to be bad, made some tests with the 200PSI air gauge... :crazy Got 30PSI on one, and 180 PSI on the other at the absolute lowest idle of the engine, the slightest amount of throttle pegged the gauge, but with such a small gauge, that's not much of a test. At the main reliefs also got no pressure on pump #1 and 100PSI on pump #2. The mechanic was telling me that these pumps were bad because the input shaft rotated freely, is that enough of a indication for a worn pump?
Those are gear pumps which means an open center circuit. Never saw a gear pump with a few hours on it you couldn't turn by hand. They may indeed be worn, but you either have to check pressure and flow on the machine or get a pump shop to put them on their test stand. You should cap the ports and give them a good clean, especially if you take them to a pump shop. Look into the ports while you're turning the shaft, make sure the gears are turning in both pumps, just for giggles. Sometime a key will shear or the coupling between the pumps can strip out. You won't see any pressure above flow restrictions and return filters unless you move a valve spool, when the machine isn't doing anything the oil just gets sucked from the tank by the pump and then pushed through the center of the valves, on to perhaps an oil cooler, then a return filter and back to tank in an endless loop. If nothing else stop by your local CAT dealer and pick up a liquid filled gauge that maxes out at 3,500 or 4,000 psi. Then check pressures with a control moved, let a cylinder hit the end of stroke and see what the needle comes up to. Don't hold it like that any longer than it takes to get a good reading, no sense heating the oil and relief valves up for no reason. Try swapping the main reliefs as has been suggested previously if you don't get good pressure on the two spool valve.