Link belt 330 2006 model 7200ish hours Been working fine, cranked yesterday, tracked about 30 yds, started drifting. Left track pretty much quit in forward
Check your pressures and check the flow of the case drain on that track
Pressure according to diagnostic screen coming from pump, is good/normal. If you’re saying to check pressure somewhere else, I wouldn’t know where to do it. Or are you saying to check it at case drain?
You mentioned the problem in forward. Is it not there in reverse?
Sorry, incomplete description... reverse operates just like it should. If I take pressure of the track, it will move in forward direction, but very slow.
check to see if the motor is bypassing oil out of the case drain. and I did not catch the problem only in forward is it the same in reverse
that rules out a travel motor maybe pilot pressure from joy stick or control valve problem
Yes sir my fault. Wasn’t clearly explained
I think I'd look for dirt under the pedals first thing but the problem really sounds like the swivel is bypassing on that particular seal. You might check case drain at the top of the swivel moving the weak track in the forward direction. Sometimes the slow track will switch sides going in the opposite direction as well. Just depends on the order of seals in the swivel joint.
I have found when you have a bad swivel the tracks will counter rotate but not drive the one track alone try that 8000 hrs it is normally time to do the swivel any way
Not in the pedals as far as I can tell. That was the first thing I checked. At the risk of outing myself , when you say swivels, I’ve got no idea what you’re talking about. Don’t run this thing for a living, just keep it here at our place for a major clearing project. Reasonably mechanically inclined, but not super experienced working on equipment, so don’t know all the terminology, or location of different systems. Usually just have to figure it out tracing lines ect. to me it acts like: 1. There’s a bypass stuck open letting oil circulate 2. Filter/screen clogged , causing same as above The machine doesn’t bog down at all, so doesn’t act like it’s deadheading somewhere. I appreciate all the insight , and help I can get after quick research ... didn’t realize what you where talking about , but do now. You mean the the motor that actually spins the superstructure itself? What should I be looking for, leak, low fluid?
The swivel is a rotary manifold that routes oil from the rotating house down through the center of the machine and to the travel motors. If you look just in front of the swing motor you will see a group of hoses connected in the center of the machine. If you can watch that while the house turns, you will see that they all stay in place with the house. If you can see below that, you can see the bottom section stays will the carbody. Judging from your comments, you should probably think about contacting a knowledgeable mechanic to give you a hand and some schooling on how the machine works and troubleshooting the problem.
Can’t disagree about needing knowledgeable mechanic. Problem is there isn’t any out here. Closest one is about 200 miles away, and isn’t real interested in helping out. So at this point, I’m stuck doing it myself
As a side note since swing motor was brought up. Usually operate in free swing mode. If not, the machine feels like it’s fighting itself a little when rotating. This is fist linkbelt I’ve ever run , so maybe that’s standard. All the rest I’ve been in didn’t feel that way. Not sure if relevant/related or not
Free swing is just that. Start the house turning and let go of the control and the house will keep on going. In standard mode the hydraulic motor has dynamic braking with the hydraulic oil. Let go of the control and the house will stop turning pretty quickly. What you might try to check for a problem is get the monitor panel in the mode that will show the engine RPMs and see if they drop down a bunch when you have the house turning full speed in standard mode.
Sounds like rotary manifold issue. It's can be dangerous if u dont know what you are doing. but u need to pin track that wont go forward (install something solid in between sprocket and track frame) lift up opposite track with boom and try and drive pinned track forward. If manifold is bypassing ur track that's in air will move.
Appreciate the info on testing. So assuming that the trick works, what the diagnosis, and what’s the theoretical fix?
If the track moves that means the rotary manifold is leaking internally. Manifold will have to be removed disassembled and resealed
Nice little trick if the leaker is next to the opposite side track. What happens when the leaker is next to the case drain port or the same side return? Now that I think about it, most travel spools now days close A & B ports when in neutral so how is the opposite track going to move if there is no return circuit? It's something I'll have to try in the future. In times long ago we would remove a hose next to the suspect and pressure the circuit we thought was leaking but pumps put out a lot more oil now days.
Id check pilot pressure right at actuator for forward movement first.
Might be blurry on details, but as far as I remember the computer stops sending release signal to swing break release solenoid couple of seconds after pressure switch for swing opens the circuit, free swing means computer sends release signal constantly. If you have restriction in swing movement you need to check the current that computer sends to solenoid in normal ( not free swing) mode, and also corresponding pressure to friction break piston. If current too low your swing breaks not releasing fully.
The swing brake is released instantly whenever any function is used and doesn't reset until everything has stopped being used for at least seven seconds in all the excavators I've worked on. You can plumb a gauge into the swing brake release and watch it work if you suspect a problem.
I learned that truck from an older guy I have done lot of work with super smart guy. It has helped me out in passed and honestly most of the time when u have had issues with slow / weak tracking and after testing and i got it apart almost every seal in manifold is damaged if not missing.
I guess in this situation with one function acting up u could be right. But it's simply enough test.
I have nothing against this being center pivot, but I think that pilot test should be done to eliminate that possibility, and it is easy enough, a lot easier then getting center pivot apart.
Folks I really appreciate all the help/suggestions so far. pilot pressure is on my list of things to do first. On a related note, where can a guy buy a shop manual/maintenance manual for one of these things. Dealer says they don’t have them. Only thing I can come up with is stuff on eBay
Go on google and search, there’s some paper back on eBay, there’s numerous sites you can buy and download and print. Make sure you get manual for correct series and generation.
If can’t find Link Belt ask people which Case or Sumitomo is the same.
I’ve tried the case dealership. They’re about hour away. They swear up and down they can’t help me as far as the downloading manual goes, can anybody recommend a good source? I’ve seen them advertised, but always leery of scams ect.
What is machines full designation, with all the the letters and dashes?
330 LX 2006 model
There’s paperback on eBay for $85
would this test work if blocked the working track, front and rear, with sand? Like chocking tires? Use enough to whet it can’t move? Little hesitant to start wedging stuff between frame/sprocket. Don’t want to tear anything up, or create flying debris. Just thinking out loud ....
All of that is a good recipe for chasing your own tail! Get some plugs and caps, hook pressure gauge, and start plugging capping the components one by one and see after eliminating which component your pressure will jump up to main relief pressure! Start with motors and go backwards.
I carry and use an old bucket pin. It fits pretty comfortably in the teeth and locks in perfectly against the track frame.
Quick update. All pressures checked out normal. On wild ass guess, pulled actuator out of drive motor. There was an internal plunger( no idea what it’s actually called) that was threaded. It fell out on its own. Had markings on it where it had obviously been tightened with Chanel lock pliers at some point. Replaced the oring, threaded it back in, closed everything back up, and problem has been fixed. would like to say thanks for everybody that offered help/suggestions