Our Hitachi EX-55 broke a piston and will not run, but to work on the engine I need to rotate the cab about 90°. I've been searching on here for the last hour and have had no luck. How do you get the boom cylinder and swing motor to move without being able to start the machine? I tried cranking over the pump with just the starter, but didn't get any movement. Unfortunatly I don't have another machine to drag it around with, but have chains and jacks if need be. I saw a mention of backing out the relief valves, but not sure what that helps with? Any suggestions? How do people notmally load a dead machine?
Not sure about swinging it dead other than releasing swing brake and then pulling around. The op manual should show that. Dead excavators can be moved by taking final cover off on outside both sides and pull center drive gear out and reinstall covers. The tracks will then freewheel.
The swing brake is spring applied and pilot oil released. Taking out the relief valves will not release the brake. Sometimes the park brake is worn out enough that you can pull through it. If you can, put a porta power on the swing brake release line and pump up to 500psi and hopefully the pressure will hold. You will need something to pull the stick/bucket and if you are lucky you have the flat part of the bucket on the ground and can drag it around. If you have to lift the boom up to clear something while swinging you will have to take the boom rod side port relief and back out the setting. Now again you need to use something to lift it up. When you lift it up in this condition you lift 3 feet and it will go back down 2 feet approx. What I am saying is you have to lift it way higher than where it will hold. Also when you get it up in the air hold it at the raised hight for a couple of minutes before lowering. If you are not on level ground you will need something to hold or stop the machine from swinging around.
What about picking up a cheap 12V DC hydraulic motor / pump and using that to temporarily power the system? It look like the pump just has two lines and a case drain, so i might be able to bypass it. Any idea what the type metric thread fitting are on these grey market machines?
There isn't another small line for the brake release? Should have 2 main lines one case drain and a brake release. You could use the 12v system. It should work. I have also heard of some guys loosening the head of the swing motor to release the pressure on the springs and turning it that way. While technically that would work, I have never had to do that as I have had a porta power.
I winched several dead hoes onto lowboys with the tractor's winch... They were all ready to be moved... the finals were out. the booms were chained together.. They uses a loader to hold the boom up as it was winch on the lowboy.. One was a 3400 Linkbelt , it had gone for joy ride into the river... that took 4 dozers to winch it back to dry land...
The two lines + drain are from the top of the pump, I'll have to look tonight if theres a brake release line underneath. The bucket is down on the flat side, with the stick all the way out. I'll try cracking the boom lines with a jack under the bucket to get it lifted up a bit, but I assume the swing brake will need pressure before I can winch it around? The machine has around 4,000 hours, how well do those brakes keep working over time? To go with the 12V pump, I assume I'd need to provide pressure to both the supply and brake lines?
Here's a couple pictures of our pump / swing from the Deere website: View attachment 77154
HI there, was just thinking could you get an ag tractor in there and plum up two hydraulic lines to one of the remotes on the tractor? They are quick attach, not that expensive and should be able to give you power to your hydraulic system. I think most tractor systems have a relief pressure in the vicinity of 2500psi. Maybe even just rent a hydraulic log splitter with a little 5 hp motor on it, that may give you enough pressure and flow rate to move. best of luck
I found the line for the brake release, it's tapped off the backside of the pump. Do the pilot lines / brake release operate at a differant pressure than the main system? I don't understand why it's a seperate line rather than just a tee off the mains.
It might be tapped into the signal line for the swash plate angle Kicker. In an idle mode when you are just sitting there the pump de-strokes and has minimal flow. But when you move a lever or go to travel you get a signal to the pump to stroke and deliver your oil flow and at the same time it releases your swing brake unless you have the optional brake lock switch.
Ok, that makes a lot more sense. I got some fittings and went to hookup the pump tonight, but found noticed another line off the pump. It appears that there is a seperate small pump attached (from line 17) that runs some of the functions, and the line into the side of the pump would be controlling the plate angle & brake. So we have a large oil intake underneath, two supply lines on the top plus a smaller supply line on the end, and a tap off the side for the pilot controls & sens for plate angle. Looks like I'll need to get a couple more fittings tomorrow so that my 12V pump can supply pressure to all four of these. I'll run a pickup tube from the tube from th tank to feed my pump. Wow, this is turning into a lot of work to get an oil pan off... Thanks for all the help so far, it's great to have forum like this!
Just found a write-up on this machine, the specs are that it has a dual axial main hydraulic pumps, and a third gear pump. So these, plus the signal line makes sense. I'll get some pressure on all four tomorrow and see what she does!
How many lines go into the swing motor? 4?
I can't see the swing motor well enough to tell if there's a fourth line, but there's at least three.
Ok, I'm having absolutly no luck with this one. I've hooked up pressure the all four of the pump lines, and also tried the two main lines plus one of each of the pilot / third pump lines. With the key on, and the safety arm down, I don't get any feedback. Not even a clunk when moving the levers. Any ideas what else might be stopping it? After pressurizingthe system, I get a lot of fluid coming back out of the lines when if I disconnect one. Probably around a quart worth of oul spurting back out. I wouldn't think these have an accumulator? EDIT: I just tested, and am able to get the blade to move up and down with the system pressurized from my 12V pump. Normally, the blade can be raised and lowered without the safety arm down, so I'm not sure why it's differant now. Nothing else moves.
There is a solenoid valve that appears to control the flow to the pilot controls. One side is connected to the safety lever arm, and the other I'm having a hard time tracing. Is there usually a electrical fuel switch or something to tell the system that the engine is running other than the key? I think the root of my problem might be at getting this valve to open.
Can't seem to edit posts to update, so here goes: Put all four lines back on the pump where they originally are, fired up the engine, and still have no pilot controls. Could something have happened from pressurizing the pilot system? There is no joystick feedback, but I can track left/right, and move the blade fine. Would air in the pilot system cause a loss of controls? How do you bleed pilot lines? I tried cracking a couple of the lines at the control valves, but didn't get much fluid coming out even when the lever are operated.
Solved!!! Solved the pilot line problem tonight! The pilot solenoid valve is somehow linked to the alternator. If the system doesn't sense the alternator putting out a charge, the solenoid will not open and there are no pilot controls. Now the machine is rotated, and ready to replace the piston!
Good job. Probably wasnt getting enough voltage to hold the valve in the solenoid.
Actually, I think it's more than that. I had the battery hooked up to my truck running, but the charge indicator light on the machine still stays on. Perhaps it actually senses off the field from the alt?
I pulled the boom around until it it released. I Assume the re is a pressure relief in the spin motor
Pulled finals, God does that **** stink.... Lowbed next.
Hope I didn't break something inside
I got to this too late but why not just pull the swing motor out and rotate the machine. The brake is in the motor isn’t it.
My Dad tells me that if the oil smells bad, it's because a little water is in there and you are smelling the oil start to rot. Same smell can be found in differentials in 4x4s that have been playing in the mud. new 90w smells nice, so I've thought he might be on to something!
It's done . Now I can swing machine around by hand....!!!!
It's done . Now I can swing machine around by hand.... Oil is clean and blue like you've never seen before. Beautiful actually. There is no water in the oil..... Gear oil gags me. Every time.