Long story short replaced swing motor with a new/rebuilt one. Swing Brake won't release now. Can someone help me to troubleshoot with a test gauge? Cheers. Tommy
Follow the pilot hose from port SH on the pilot signal manifold to the top of the swing motor. Install a tee fitting and 1000 psi pressure gauge. Pilot pressure to release the swing brake should be 550 to 580 psi at high idle. . .
When I put my gauge here I am getting 500 + psi on my gauge when I try to swing.
What was the issue with the original motor ? Whats the pressure at the work ports when trying to swing ? You can check hydraulic pressures in the monitor.
The original swing motor piled up inside. I have lifted the new motor up and visually confirmed that the motor will not spin. While still connected to all hoses. I took pictures and color coded zip ties. I have the Dr.MP software just learning about the monitoring features still. What are the work ports you mention? Thanks for the help on this. Cheers Tommy.
I get hardly any readings from this port. I assume is case drain ?
The work ports are the 2 high pressure hose connections at the head of the swing motor. Where does the small hose end ? What did you do to clean up the circuit/system after the motor failure ?
The small hose runs back to a manifold that runs to the hydraulic oil tank.
are these the two high pressure lines? If so I'm not sure how to hook up a gauge to these lines.
You need port plates to physically check the pressure on that flange style hose connection. Check the hydraulic pressure using the monitor (or your software) . Run boom or stick over relief to confirm the main pump pressure sensors are working accurately. Should be around 34-36 mpa (both pumps) Swing over relief should be around 33-35 mpa.
As far as cleaning up the circuit/ system what should be done? I changed the filter in the tank. I assume that's not nearly enough. How do I check pressure with the monitor? Thanks again for all your help. I will need to find "port plates". So most likely I have trash that's gone through the system and blocked something else. Cheers Tommy.
HEF member @John C. has a YouTube video on using the ZX-3 monitor .
Thank you! And here I thought I could only see that info through the laptop. I'm heading to the machine now it's a bit remote. What should be done to clean the system? Please don't say drain all the oil . New Pilot filter at least?
Sorry it's so hard to see. Hit 31 on avg on both pumps however it wasn't always consistent sometimes pump 1 was hitting in the 20's. When I went to pilot / swing it was only reaching 4 maybe 5 MPA.
IIRC pump #2 supplies the swing. What is the pump #2 delivery pressure when you are trying to swing
5.0 mpa up to 7. Saw spikes up to 10 or 13 almost when letting of or feathering the controls on and off.
I suspect the swing spool in the main control valve is sticking / jammed with debris from the original swing motor failure. Remove the swing spool and check that it moves freely in the bore. As far as a “clean up“ goes, at a minimum I would drain the oil and clean the bottom of the hydraulic tank. Remove the hydraulic filter and clean the bottom ledge of the filter housing. Replace the pilot filter. Check and washout the removable suction screen in the bottom of the hydraulic tank. Fill with new oil , bleed the air from the hydraulic pumps. Remove the 2 swing supply hoses at the motor. At an idle flush the swing hoses in both directions. Reinstall the hoses and see what happens.
I'm still at the machine do you have a diagram of said spool location by chance? Otherwise I will research when I get home. Thanks for all your help. I owe ya a few cold ones.
Follow the 2 large swing hoses back to the main control valve. The vertical swing spool is set back a couple of inches but lines up with the hose connections.
the swing spool is under this cover.
I believe this is what you mean ? Sorry kinda learning as we go here.
I think the swing spool is #70 at position “e” in the control valve. Remove the one-piece cap #5 and the spool comes out the top. The screenshot is from the Deere parts look up site. https://partscatalog.deere.com/jdrc/sidebyside/equipment/76695/referrer/navigation/pgId/541277135
Thanks pal. I'll open it up another day. Its a mess on top of there.All kinds of muck and grease and debris. I imagine opening the cover iup is not a good look. I plan to get a dewalt portable pressure washer and clean that area off before I open up and contaminate anything else.
I went back and cleaned the area off with degreaser and a portable pressure washer. I pulled cover number 5 and pulled the left most spool. It looked normal (to me). I pulled the next spool beside to compare and I noticed nothing unusual no debris. Any ideas on what to check for next? You said in your original post the brake was looking for 500 MPA or so to release?
I said 550-580 PSI at high idle to release the swing brake
Sorry meant to put psi. Wasn't sure if there could be something mechanically wrong with the pump. 500 psi is only like 3.4 MPA. When I had my gauge on the top port I was getting a reading of 500-550 psi when trying to swing. Do I need this pressure to come from the working ports then?
Finally found a good diagram of the control valve with all the functions labeled. Just to confirm you had the swing spool out looking from this orientation ? .
Yes sir. I took the swing spool out. It slid in and out easily. There was no debris present oil looked clean. I also took out the arm 1 spool to compare apperance. My travel is slow as well. I plan to get the pilot filter today and more oil. Is it possible that this is caused from air trapped in the system?
What’s the pump #2 Control pressure when trying to swing Left and right ? Should be around 3.5 mpa. Most all of the functions when over relief the pump Control pressure should be around 3.4- 3.8 mpa
Is that different from delivery pressure? I can check at lunch I'm just down the road working a different machine.
Yes, it’s pump Control pressure. You should be able to look at pump #1 and pump #2 control pressure on the screen at the same time.
I don't know if I can post a videos? I'll post a screenshot. Surprisingly pump 2 is hitting 3's. And pump 1 isn't doing alot of anything. This is the same result trying to swing right or left.
Pump 2 control is good, Pump 1 is ok where it is, it’s not used with swing. Can you repeat the pump 2 Delivery pressure when swinging left and right. Has this reman motor ever performed properly since it was installed ?
Sorry screenshot again. This is delivery pressure. Does the same swing left or right. Averages about 5mpa some spikes to 10 when starting and stopping joystick to swing.
Has this reman motor ever performed properly since it was installed ? I would check swing motor case drain leakage. Case drain leakage is 2-5 litres/ minute, maximum 5 litres/ minute.
No it has not. And it came from a contact in China. My gut told me to open it and inspect it before installing it. I took the top off and everything looking brand new inside. Do I need to dig into it deeper?
I would check swing motor case drain leakage. Case drain leakage is 2-5 litres/ minute, maximum 5 litres/ minute with motor stalled. . Case drain hose I marked in red.
I am betting you did not get the top valve plate installed properly on its locating pins when you reinstalled the top head. I know , I have messed it up myself !! .
The first time I messed it up and the top valve plate got slightly bent. I cleaned up my old one and used that. The second time I was 99% confident I got it right. And kept the plate sticking. You have a trick you use to keep it stuck when you put the top on? But I also installed the motor when I first got it before I ever opened it. And it was still not swinging.
I just use white grease on the back side to hold it in place. White grease seems to work best as it is the most tacky. .
So just remove the hose and let it flow into a bucket and time it type deal ?
Yup exactly , measure while attempting to swing and engine at full throttle
One last thing here before I try that out. Could anything in here be a problem. I used the old one of the old motor. Also when the motor first broke. I got pissed off threw it in HP and tried swinging back and forth. Well it split the motor casing and obviously started pissing hydro oil out. Could I have damaged a relief valve?
I believe they call that a cushion valve , can‘t see that producing a no swing situation. I think the original motor case got split by a piece of motor shrapnel getting jammed in the rotating works.
If you really get down to questioning it, just take the entire cushion valve off temporarily for a test. Reattach the hose flange clamps using shorter bolts.
yeah at this point I'll try anything. I have another mechanic to bother, that did my pinion seal,but he's a few hours from the machine, he suspected the swing spool being contaminated with trash from old motor as well. But now I'm really questioning this motor as well. Is it possible this motor is hung up as well? Old trash contaminated new motor? Anyways I won't be able to sleep tonight without trying the case drain test. I'm heading out right now to try it. I got a new pilot filter today at lunch. I just figured until I solve the no swing issue, i'll wait on changing out the fluid. The hydraulic oil was done 150 hrs ago. doh! Is there a pilot pressure reading I should be looking for in the monitor?
I need to cap the end at the hard pipe where I remove the hose correct ?
Yes.
**** any idea the size? Motor supplier wants me to test with out the cushion valve now
In the monitor you could check “Swing Control Pressure” That would be the swing pilot pressure sensor at or near the spool cap . We have not thought of or checked that yet !
One sec, I’ll check right now
What pressure am I looking for will try that before removing cushion valve
I think I am incorrect when I said the large hose on top of the swing motor was the case drain. It is actually the “make up“hose. I believe the case drain is the small hose you pointed out yesterday on the side of the motor. I want to say you will need a -6 or -8 JIC cap.
500-580 PSI.
3.5 - 4.0 mpa
Awesome I think I have a cap. I didn't want to question it lol. Here are the results from the swing/front attachment control pilot pressure .goes from 0.2 to 0.4 mpa You can see swing pilot pressure as well this is the same for swing left or right. It goes to 4.20 moa
Hold the phone… The swing front attachment sensor should be reading around 4.0 mpa also. That is the sensor that reads the pressure releasing the swing brake. The sensor is located near the top of the swing motor case. Is the wiring disconnected or the sensor broken off ?
Wouldn't that throw a code?? I'll go inspect it.
If everything looks ok with the sensor , you could swap it with the arm in pilot pressure sensor which is located on an end of the 4 spool side pilot cap on the top of the main control valve.
There is a sensor below the case drain hose on the motor case?
That would be it. The swing/ front attachment pilot pressure sensor is on the swing motor case
When I first installed the motor that code came up. Sensor wasn't plugged in all the way. I cleaned it off seated it fully cleared the code and haven't seen it come back ? The wiring is suspect around it that's for sure could it be shorting on itself and not throwing a code ?
The sensor could be bad also with out throwing a code. If you had time you could swap it with the other senor I described in post #66
Swapped sensors no change. Everything works but swing
The large hose on top of the motor is make up, the smaller hose on top of the motor is case drain. The hose that goes into the side of the motor is brake release
Hey Johnny welcome to the party pal! These lines were color zip tied and pictures were taken before old motor was removed. I'm positive this is how it was plumbed in before. Will swapping the hoses wreck anything to try this out?
This was before I took the old motor out and exactly how it is now.
Im going to say thats plumbed wrong. If i was there and wanted to confirm though, id find a parts pic showing the hoses from your hitachi or john deere dealer. Id also recheck my brake release pressure with the hose disconnected from the motor to be sure its not excessive case drain pressure you're reading off the top of the motor. You should see your release pressure come up to 600 psi any time you swing or hit a dig function, and it should drop back to 0 after about 5 seconds after you let go of all functions. If you put brake release pressure into the case you may blow out the shaft seal on the motor and fill your swing drive with hyd oil, but then again you may get lucky and not. Also, this wouldn't be the first time hoses have been marked incorrectly . Im going to say im 99% confident that the top small hose is case drain though, and the -6 that goes into the side of the motor where the sensor is, is swing brake release. But ive been wrong before
I dont have my laptop with me right now or else id confirm for you
It just doesn't make sense to me how it worked before. I took that picture before I touched anything. According to this I think you are right that these lines should be swapped? Oh wait this is for an EX 200.
Ya swap the hoses. Someone has obviously been into that motor before you
Once you swap the hoses and get it moving recheck your swing pressures. You may have 2 problems
Yep the guys that did my pinion seal pulled the whole swing assembly. Is this why my swing motor failed. I just don't understand how it worked for 100hrs. Before grenading.
Also, always troubleshoot at low idle. Youll never blow up a housing that way
Id fix it first, and analyze the sequence of events after
I swapped the hoses my swing/attachment control pressure now matches swing pilot pressure. But still no swing?
Whats your discharge pressure off your pump when youre trying to swing now?
Sorry you have to talk to me like I'm a 4 year old with this ****. That's full swing right low to medium idle.
Thats both left and right? And what is it when you hold boom up?
Yes. But now they match around 3.90. First pic trying to swing right or left Second pic Boom back to full relief 32mpa
So did i read somewhere that your valve plate is damaged?
Yeah when I was stupid and took the top off the fresh motor because I was determined to blame China for a bad rebuild and the no swing. Guessing I didn't put it back together again right the second time
its pretty easy to confirm if its the valve plate by checking case flow out the motor. Take the case drain hose off the tank and hold it in a pail while trying to swing. A good motor will have case flow like a garden hose with the tap opened 1/4 turn or so. Flow but no force coming out. If oil comes out like a firs hose pull the top and look at the valve plate
And I've likely blown the seal out pumping 500 psi of pressure through the motor the wrong way?
Took this hose off "case drain". From top of swing motor. Capped manifold. Started machine engaged pilot lever.jug filled with oil and overflowed in a second. I shut the machine off as it emptied the hydraulic tank all over the ground
Yeah, you should pull the cover back off that motor and have a look at the valve plate
Yep wish I didn't have a gutless DeWalt impact gun. Hopefully I can get a breaker bar in those bolts anyone know the torque specs for later.
Yep failure on my part.
******. Are you going to try and reuse it or order another?
You are going to want to tighten those up by hand, don't use a gun or you're going to regret it. Im speaking from experience ♂️
Can I even ? Maybe just to troubleshoot the no swing ? Is this the cause for my no swing you think ?
Took a 3/4 inch impact air gun to get the old ones off so I thought they might be torqued down something heavy.
Most likely the second part if your problem, yes. Im not recommending you reuse it, bit if its flat and youre panicky for the machine?
Yeah, i pull them down with a 1/2" ratchet then tighten them up with a big snipe.
Ive reused them in a pinch....
when i put them together, i try to suck the oil out of the motor housing and dry the valve plate and head off really well with brakecleen and a rag. Then i use the stickiest grease i can find to glue the valve plate up to the head, and then very carefully pull the head down with a ratchet. If the valve plate drops while youre tightening the head down youll hear it
Oh you put the GRRR in Swinger baby ya!!! Man I'm so pumped it swings!!! I flattened it out with my big hammer and had to touch it a bit with a grinder. Thanks a million Diesel Dan and Johnny Canuck I owe you guys a case of beer each and then some.
Good deal, im glad to hear you got it working
Team effort ! Good to see you are back up and running Tom.