I have a case 2007 cx36b , got it about a month now, the left track is slower than right, took pressure readings from test ports on drive motors , both sides were pretty much the same, low speed 500psi free wheeling, high speed 1000 psi free wheeling, dead head pressures with track pinned was 1100 psi low speed and 3100 psi in high speed . the pilot travel valve has full movement , got to pull case drain line and check flow and amount hyd oil next. and if I have to',cross hyd lines from left to right side and see if that follows to right. If so the left final drive or motor is going. Any help would be great, really scathing my head, I don't want to start throwing big money unless I really know what's wrong. Thanks Dennis
I hope someone replies to your post. I have the same year and model with the same exact problem.
Good day Guys Suggest you check out for mechanical faults it may be for example a failed idler bearing or transmission issue, you can get the complete troubleshooting information at excatech.org > Library > Common defects > weak crawlers download or read it may well help. We are around if you need more help. Kind regards Uffex
Corey have you had that machine for some time, if so did the problem develop slowly, and have to done any trouble searches, I will kept you up to date when I fix this. I bought this machine about a month ago knowing the track problem , got it from a dealer
Hydraulic pressures for dead heading the tracks should be the same in both high and low speed.
John, I thought that the pressures is what makes the high and low speeds different, when I freewheeled the tracks there was a pressure different in high and low travel speeds of 500psi these mini excavators have several different pressure systems . Thanks
Two speed is usually achieved by changing the angle of the swash plate in the motor. The flow to the motor is the same in both speeds. The pressure reliefs are the same. High speed shifts the swash plate to half stroke which increases the rpm. You should have four hoses going to each motor.
Yes 4 hoses foreword, backwards, speed changer and case over pressure hose. When I tested pressure I used the testing ports that are pugged on the drive motor, I did not test from the foreword or backwards hoses, should I test directly at hose ends, if I test from hoses it will be a deadhead pressure only unless I install a tee , but that would be the same as the test ports ???. Going to test case over pressure amount of oil . Do you have any suggestions I check track slack, the machine has a newer track on the left side , same side the problem is , came like that. Thank you for the information . Dennis
You test pressure at the pump. There is no over pressure hose, it is called a case drain. The travel motor reliefs drain into the down stream hoses feeding the travel motors. You check the case drains by removing the hose at the motor, locking up the track and then running the motor over relief. A good motor will have less than a pint of oil in a minute of stalling. Case drain is the oil that is leaking inside the motor from the supply to make it turn. A difference in the length of the tracks can cause the machine to veer off to the shorter track side. FYI: Below is an educational video about excavator undercarriage.
I have a CX36b and had a CX50b, both tracked slower on one side after about 2000 hours. Both were open cab machines, both had corrosion and wear in the pedal linkage where the pedal rocks forward/reverse to work the travel. There is a little rounded surface on the underside of of a metal block at the bottom of the travel lever/pedal assembly where it goes through the floorboard, mine were rusted and had a flat spot worn that prevented full stroke, but to different levels on one pedal than the other, so faster travel on one side. Worth taking a look.
These machine were notorious for bad travel pedals, I've seen one with a bad swivel the rest were pedal related. Raise the window , don't start the machine. Clear away any dirt and remove the floor matt if it has one. Now using your finger press on the right then the left pedal forward and back. If one seems to have spring tension and the other side does not it's in the valve itself. The repair kit is more money than a new travel valve.
I have a open canopy, all ready cleaned pedals and replaced the boots. I did your finger test and the right side lever [ which is the good side] moved freely, but the left side [ the problem side ] was different, like it didn't fully go back to neutral. some thing to look in to. Thanks for the info. The old boots were ripped , like muddauber said might be corrosion on pilot valve spools thanks guys will let you know on results .
I'm in the same boat. I just bought it two weeks ago knowing of the track problem.
Check under the pedals for anything that could limit their travel.
The left side that doesn't neutral is an internal problem with the springs and spools, it's new travel valve time. Parts are hard to get or impossible and the price is ridiculous.
Going to get in to it next week, a rebuild kit from case is $385.00 and trying to find a pilot valve in the USA, is imposable, you can get one from over sea's , never bought from over there, a rebuild kit will work as long as there is no corrosion ,
How many hours on you case corey, I have had three 580's in the past and never had any big problems with them, I really like case equipment, that's why I bought this cx36b knowing the track is issue , I have 3300 hours
I got just a little over 1200 hours on the cx36b. I really like Case Equipment too. Got 2 580k's. 1 580sm series 3, 9010b excavator, and a 1150e long track dozer. The backhoe's have been trouble free for me.
Case must have gotten better on their pricing the kit use to be 3/4 of the cost of a whole travel valve.
IF the valve is corrosion free I will rebuild but if damaged will have to find one, have you or any one flowing this post ever bought parts from over seas. pro and con's please Thanks
I found a pilot travel valve from case in Ohio. I bought it even if its not my problem, was told there was only 4 in the USA very lucky
Pulled the case drain hose on the slower side , lock the track and dead headed for 1 min. got exactly 16 OZ. of hyd oil, I think this is ok, case book say's 30sec's .40-.79 gallon is ok . I pressure tested the pilot solenoid valve, I think this is the high speed valve, any ways the valve had a test port to install a gauged , the book says you can use a gauged that go's up to 1000psi. The running pressure was a little over 505psi, book said any pressure at 505 psi or over is ok. I said early that the machine came with one newer track on it, the slower side is the side with the newer track , I going to swap tracks and see what happens, and will check under carriage, if I swap drive hoses, I have to get more hyd plugs,
John, you where right, I re tested final drive motors with a new gauged and pined track all dead head pressures where 3,300 PSI . Thank YOU
Dennis, you mentioned there were 3 pilot travel valves left in the states. I need one and my local case dealer can't find one. By chance do you remember who had them or get me in contact with the person that said there were 3 left. Thanks
Corey I bought it from [email protected] contact person Ted Persing 614-357-2017, It was a genuine case part, I did everything on line , didn't have to call , I was told by Rich Lobdell from [email protected] that southeastern had three I bought one, The other case dealer on capecod mass. had sold there's . My I ask why do you need one did you find the problem, I am still scratching my head
Corey I forgot the number for southeastern is 740-432-6303 / 740-446-3910 / 740-374-7479 that is what rich e-mailed [Good luck ], let me know how you do
my travel levers don't center properly. They just don't feel right. From what I've gathered on this thread these machines had problems with those Pilot Travel valves. Being that mine does not have a cab and has sat outside since it was new prior to me owning it, I just wanted one on the Shelf in case I find a mess when I open it up since they're hard to come by. Thank you for the information.
Can any one help me and point me where I can get my final drive motors running pressures , free wheeling Thanks
I've never seen where running pressures will tell you anything. It's the flow off the pumps that determine if a machine will run straight. If your travel motors are efficient, the swivel is sealed properly and the valves are opening to the same extent, then the balance on the pumps, if you have more than one, will need to be looked at.
John thank you, I pressure tested one of the main pressure lines going to the main spool valve, I dead headed with boom bottomed out the relief pressure was 3310psi, this case has one pump, 3 pressure lines two with a relief pressure of 3330psi [book says] the other has a relief pressure of 2900psi. The line I tested has the left travel spool , boom, bucket spools. I pulled track off on problem side and checked undercarriage every thing was good, ran sprocket only and could see it slower than right side , drained final drive very very little metal fines . If I am getting these pressures all pretty close or the same wouldn't that tell me my swivel seals are ok,and I put that new travel pilot valve in no change. All the relief pressures where the same low and high speed on both sides like you said they should be that there tells me my swivel is ok. good way to spend my vacation week. Any more ideas would be great, thank you for your help
According to the Case advertising documents, your machine has two pumps within a single case. A photo of the pump might help in determining what exactly you have. Here are a couple of questions you can think about and test. Which track is slow? Is it slow in both directions? Does the slow track change sides when you change direction? The best way to check the travel is to walk it up a hill with the sprockets on the down hill side. That will take more pressure to move the machine up the hill which will change the flow outputs on the two pumps and make the problem a lot more obvious. Write down which track is slow when you do this. Travel back down the hill and turn the carbody so the sprockets are at the front going up the hill. Write down which track is slow this time. Do you have any service literature for this machine? A service manual with a hydraulic schematic would sure help.
I know that %90 of the time the travel valve was the problem if it didn't center properly I've seen lots of those. If it's still slow probably the swivel. Block the sprockets and remove the drain line compare the RH and LH sides if it's in spec then the swivel is the problem. Looks like you said it's in spec so time to think swivel.
OK guy's I just crossed the main lines from main spool valve I switched the left foreword/ backwards lines to right side and right to left side, now the main spool valve in before the swivel , well the slow track crossed and it's on the other side now, well I know it isn't my final drive RIGHT, swivel rebuilding time?????????? thanks you guy's
The ad sheet shows two main pumps and a gear pump. The two main pumps are handling the high pressure stuff with each pump feed one travel motor. The gear pump handles the pilot system and probably the back fill blade. https://www.casece.com/emea/en-**/products/excavators/b-series-mini-excavators/models/cx35b Your problem may be in the swivel but also may be the pumps being unbalanced.
John, I am going to test the other pressure line that feeds the right side track and other things , in the process of finding a rebuilding kit for swivel , can I balance the pumps the relief valve.
You can only balance the pumps at the flow controls on the pumps. You need a flow meter to do that or knowledge of the pumps and how fast things are supposed to run plus knowledge of the regulators and which adjustment do what. It isn't something most operators would know about nor should they attempt to adjust. Most of the time when pumps are out of balance it's because something has gone wrong inside the pump.
OK John I pressure tested both p1 and p2 feed ports that feed left tracking and other's and right tracking and other's both relief valves pinned out at 3300psi there was a difference of 250-300 psi from left to right when I freewheeled the tracks in low and high speed . Could I be loosening that pressure in the swivel . All tests where done on p1 and p2 feed lines on test ports on main spool valve bank. I can't see any thing being wrong with pump that feeds the left side [slow side] because the boom works off same feed and I can pick up machine off the ground like nothing . I don't know
The more I think about it is not the swivel ,I proved by switching the travel motors lines, the problem switched sides . Step in any body PLEASE, John feedback please.
I don't know the lay out of the seals and lands in your swivel. It might mean that all you did was swap the pump on the lands in the swivel as well. Usually when the swivel goes bad the weak track will switch sides when changing direct of the machine so on first thought it doesn't sound like the swivel is the problem. I know that doesn't help you because the alternative is the pumps and you will need professional help with that. Good Luck
Did you figure out your travel problem? Was it the swivel?
Also curious as I have been following along.
I pulled the swivel about 1 1/2 weeks ago, the construction co. I work for has me going all over the state working long days , no time to work on case, plus it took about that time to get all seals and o-rings, got all parts today and of course I have to work this weekend, A case mechanic told me it could be the swivel when I told him about the hose change over with problem switching to other side. I have swivel all apart and really can't see any cut ,torn or damaged seals was really clean the case tec also said to check the relieve valve thats in that circuit , also he said check pressures right on the spool valve that runs the problem side. I really have to get going on this ,I just got a flail mower for this machine , I will post any news
Corey did you get the pilot valve
Only one pump with two ports operate boom and tracks. One pump is pilot and one is blade. P1 and p2 are one pump. If problem moved it's not the swivel its most likely main relief or valve issue. Dead head boom sections related to p1 and p2.
P1 and p2 first pump then 2 gear pumps
Not yet. I'm in the process now of removing and inspecting mine. Thanks for keeping us posted.
Does any one know where I can get a quick coupler, pin grabber type new or used for my cx36b. Any body who sells them are out of stock and 6-8 week restock time
Finally got all the seals for swivel and finally got some time to finish rebuilding swivel and installed it today, guest what it wasn't the swivel. I pressure tested right on the travel spool valve ports and got 3300 -34000 dead headed PSI. Can't be the travel motor because when I swamped left and right drive motor hoses at spool valve it changed sides.
John you were right it was the pump , this is what they found, valve plate had deep grooving between ports, cylinder block had one deep score all around , swash plate balls had severe pitting, pitting of scockets in swash plate, the gear pump was good Thank you for your time Dennis
Thanks for stopping back in. This is invaluable stuff to get it all together.
Any chance you or any other CX36B owners could give a brief writeup of how to remove the swivel joint? Do you have to pull the cab/canopy to get to it? Mine appears to be leaking. I haven't worked on excavators much - not even sure how to pull the swivel out on this one. I can see the bottom of it by pulling the belly pan off. Am I missing an easier way to access the swivel? Taking to a dealer is out of the budget for me so if it's something I can do myself then I need to learn how. Thanks to anyone who can shed some light on where to start.