I just got a link belt ls 2650, pretty good shape I think, except that the slew and left travel functions don’t work. The boom, stick, curl and right tracking work fine. The pilot hoses seem to move and you can hear fluid moving when you try the two functions that don’t work. The simple schematic I have seems to show the stick cylinder using the same pump as these two functions, so I’m hoping it’s not a pump issue. Wonder if anyone on here has and ideas where to start? Pretty sure it’s the same as a 9010b Case except for the Isuzu motor if that helps. Thanks in advance Mike
Edit: It’s the same as a 9010, not 9010b
So, it looks like this forum got spammed hard right after you posted. Mods are probably trying to get that cleaned up. That's probably why no response. Personally, not much experience with LBX. A little with LBC, mostly RTC pickers. It sounds like your left side controls are lazy. That could be several reasons. Crud in the pilot valve, pinched or obstructed LS line to the pump, bad pump regulator or generally damaged pump. Are you running in ISO or backhoe controls? Do you have a pattern change valve? Is your machine equipped with a case drain filter? I don't have any details on your machine so any suggestions will be strictly generalities across all product lines regardless of mfr. Your machine may vary and I have no way of knowing.
Thanks for the reply. No pattern changer, iso controls. Like I said, stick works fine and I think it’s on the same pump. Around 7k hours, rest of machine is tight and runs like a watch. It was well maintained. Not that it still couldn’t be the pump but I sure hope not Thanks again
Ok ISO puts stick on left joystick and it works. But does it have good cycle times. Boom up and arm in are usually 2 pump flow 1 & 2 join together for quicker times. You may have good work force but poor flow. Do you have gauges to make comparisons?
I have a pressure gauge for pioneer couplings or whatever but not to fit whatever that port is on the machine. The stick seems normal speed and works with boom at the same time ok. Hard to tell for sure though without gauges I know. It pulled itself on and off the trailer though. Again, only shows good work force. Guy said he parked it for the night, started the next morning and it was like this. If you hold the lever to swing, one guy can push on the bucket and spin the machine on the level. It doesn’t even try to swing even a little. Just takes the brake off.
Maybe take pics of your test fittings, we can help you identify what you need. Amazon and ebay have decent little kits for fair prices.
Ok will do thanks.
This is the only test fitting I can find so far
That looks like the old cat fittings. Cummins compu-check. Parker PD series. I would google the parker, see what comes up. Make sure if you get a kit that it's for excavators or hydrostatic machines. You want the higher pressure gauges. Not automotive.
I don't know about the rest of your machine. Whether it's JIC or ORFS. Being LBX it might all be parallel pipe.
The 9010 I used to run I know the hoses were BSP. Thanks. I saw a Parker pd I thought that was probably it. I’ll order that one.
Ok so I found in the manual I have where the test ports are for the first and second pumps, right on the pump body itself. The inner pump showed just over 2000 psi when cycling the controls, the outer one zero. Wouldn’t even wiggle the needle. I tried every function except travel. Should I be pulling the pump apart or no? One guy said he’s had pump shafts break in cold weather. Let me know what you think. Thanks in advance. Mike
That's not good to hear. Pump should never be zero, should always be some "standby" It certainly sounds like the pump shaft has failed. I sure hope there's maybe a splined coupler or something. I hope the rotating assembly hasn't shed material through the system.
I split the pump and I don’t see any problem with the splined shaft between the pumps. The front pump didn’t show any pressure either until it called for oil? I was wondering if it might be whatever strokes the pump?
Can you attach a pic? It is a piston pump, right? Not a gear pump? Typically, there will be standby pressure in an unloaded running system. Some mfrs use this standby to generate pilot oil through a pressure reducing valve, others use a stand alone pump to supply pilot. The pilot oil travels through the safety solenoid to get to the joysticks and pedals. When you demand a function, that pilot oil goes through the joystick/ pedal out to the main control valve where it pushes on one side of the spool shifting it out of neutral. Depending on pump control it will either bleed off control pressure or increase control pressure to the pump regulator. The regulator will stroke the pump based on demand vs pump pressure. Maybe the pump regulator yoke broke where it actuates the swashplate. What's concerning is you said both pumps show zero pressure with no demand, that doesn't make sense unless you maybe. have a defective gauge.
There are two stacked piston pumps and I think a gear pump for the pilot pressure? It’s just a farm store gauge.
Not a great picture
Maybe look at the regulators, if you're not seeing shrapnel and carnage we should be looking for a clean break. Maybe the pin to the yoke. Thumb through your manual to see if it explains better or shows an exploded view.
I was videoing the gauge when I was running it, I just looked again and the first pump does show a little pressure at idle with no demand, couple hundred pounds or something. The other one shows none.
If the solenoid that strokes the pump was bad would it still show some pressure or no
Yes, standby pressure should always be present. But, BUT... It depends on where you're measuring. The solenoid doesn't stroke the pump, it throttles the pump back to prevent stalling the engine. Are you measuring pump discharge pressure? We'd have to look at your schematic. I believe older LBX are negative control. Meaning you have full pilot pressure keeping the pump at minimum displacement as you demand oil, the control oil is bled off through a jet in the main control valve, which strokes the pump up. Negative control are so much smoother than positive in my opinion. The fact that you say when you ask for swing, a guy can turn the house by hand says that pump has no displacement or pressure. The brake is released by pilot oil and the hydrostatic brake is broken when you shift the spool so a passage to tank is open. Did your manual happen to show an exploded view of your pump? Or a better description?
No it just shows the pump in like dotted outline. The ports I’m measuring from are two ports on the top of the pump, in between the two pumps themselves,threaded holes in the pump body
So the pump should have some resistance on the swing regardless of pilot function or solenoids, etc?
I guess would you pull the cover off the pump itself and look? The pilot gear pump looks easy enough to take off.
Is the pilot pump piggybacked off the main pumps rail end or on the pto separately?
It’s bolted right on the second main pump
So that guarantees the shaft is good. The yoke or regulator must be harmed. Wish I'd bought those x-ray superman glasses from the comic book.
It pretty much has to be a problem with that second pump, right?
The regulator is the block bolted to the side of the pump, right? With the solenoid on it?
I believe so.
I agree on the x ray glasses.
The Best Way to Learn Practical Hydraulic Pump Troubleshooting This page describes the best way to learn hydraulic pump troubleshooting and provides an example of a diagnostics of a Danfoss series 90 closed-loop pump. www.insanehydraulics.com I know this looks sounds like a cop out, but I kinda want you to know what you're getting into by "going into" the pump. Check this man's blog, he's a member here. All kinds of solid and basic information to help avoid costly mistakes. I don't know if you have Kawasaki, Danforth or oil gear pumps. If I had to guess, Kawasaki. Hope you find some good nuggets of wisdom that you can apply through what your service manual has to offer. I believe your rotating assembly is somehow at 0° with no displacement. Whether that can be corrected by a controller or link, I don't know. Please keep us advised as to what you find. Obviously we are here to compare notes with, should the need arise. Good luck. In case it isn't obvious, the first paragraph is a link to a separate website.
Ok thank you
Interesting. I will keep u updated when I find more out.
Ok I got the manual Thursday, took the rear pump off today and disassembled it. Pretty much cooked.
Well that's a big bucket of suck.
Not to pile on, but I hope you got one heck of a deal. Gonna take some dollars to fix this one up right, and it'll never be perfect with the metal in the system.
Yeah….i agree.
Any opinions on those Chinese pumps from eBay? Only “yard” that said they had a pump was this excavation emporium which I’m pretty sure was a scam.
Only to get it functional to sell at an auction.
Can anyone suggest any salvage yards? Tried a few that have nationwide networks and no luck. PSV263T1 is the KYB number, used in Link-Belt, Case 9010 and JCB.
Just to update….i found a place that has been converting these machines to use a Kawasaki pump like on the next newer generation machines. It’s not cheap but it sounds like the only option as parts for the kyb pumps aren’t available and I can’t find a used pump anywhere. The machine is in good overall condition with newer undercarriage and one final recently replaced, and bucket pins were line bored so I think it’s worth fixing. They sell a kit but I just ordered the pump and will do the rest myself. I will flush the system according to their procedure. Supposed to be a good long term fix. I’ll keep you guys posted on how it works out, it’ll be probably a month or more.