Case CX 240 Hydraulic engine stall

[Tom Ellington]

View attachment 255117
It's a low pressure sensor for your pilot controls. Can you swap it with another one and see if the fault code changes.

Thanks again for your help. I can’t tell from the picture but do you have that part number?

 

[Kobelco ireland]

Part no. KHR10790
If you go on fleabay etc you will find them cheaper. There are two of those sensors on your machine one for the upper functions and one for travel. The fault code is saying either one could be gone or it could also be wiring.

 

[Reinis Zelneronoks]

Hello. But isnt that the pump has only one solenoid on the botom of the pump? It is old model for electronicaly controled regulators for the pump. Have you checket the servo pressure on the machine, cous i thik that this pressure switch is only the indication for the loss of servo pressure.

 

[Tom Ellington]

Thanks for your replies. So I replaced both sensors for the uppers functions and travel. That cleared the code but the stall condition still exists. When any function is activated, (travel, anything, if you go hard it will stall engine at 3600-3700 psi for both P1 and P2 pumps. Definitely not fuel related as mentioned multiple times fuel pressure at the VP44 pump is 13-14psi and the throttle is instant when you let off control before engine stalls. So now no codes in diagnostics, all filters on machine have been changed. Desperate for any help.

 

[Reinis Zelneronoks]

At first you should check main relief valve cous reliefe pressure is 4980 psi (Im used to metric, at first thoug that the pressure is ok). Check that the orfice is not cloged, and the neadle is not worned out. Cous pump starts to reduce flow when it reches aprox. 4600 psi if it cant reach it the flow is not reduced. Aded a picture of the valve.
Second is taht the horsepower controle isnt working properly. On the bottom of the pump you should have a solenoid ( aded picture below). Next to the solenid there is 1/4'' check point. 0 bar max flow, +-39 bar (servo pressure) min flow if you disconnect the solenoid there should be 39 bar if the sonenoid works properly. It will show error, but you can run it like that just tu check if it is still stalling.

 

[Tom Ellington]

Thanks Reinis. But I thought there were 2 separate main relief valves, one for each pump. Both pumps are stalling out at roughly the same psi when a circuit for each pump is loaded to engine stall. Leaning more towards injector pump although the dozen or so VP 44 pumps I have had experience with in the past simply died and would not even start the engine when they failed.

 

[Reinis Zelneronoks]

I might be wrong but usualy there is one relief valve for boath pumps.

 

[rmllarue91]

I don't know how these pumps are regulated off top of my head but I've ran into a few older machines that regulators where frozen internally some i disassembled cleaned resealed some changed regulators some just changed pumps. I'd imagine that uses computer electronics to control a pwm solenoid that controls pilot pressure to pumps but could also have solenoids in pump regulators. You need to study system determine external pump regulation is changing then go after pump regulators them selfs. Computer is going to need to see rpms and pressures to regulate can u verify they are working on screen

 

[Tom Ellington]

(Second is taht the horsepower controle isnt working properly. On the bottom of the pump you should have a solenoid ( aded picture below). Next to the solenid there is 1/4'' check point. 0 bar max flow, +-39 bar (servo pressure) min flow if you disconnect the solenoid there should be 39 bar if the sonenoid works properly. It will show error, but you can run it like that just tu check if it is still stalling.)

I disconnected this sensor and made no change. But I think you are on the right track as the diagnostics in Chk 2 shows the engine stops at exactly 50% rated power, as if the ecm is definite derating the power. When you unload from any control the engine instantly climbs back to governed rpm of approximately 2000rpm. Once again the engine will stall at 3600 psi from both P1 and P2 pumps when the corresponding circuits are activated. I am now positive this is not a fuel issue, 14psi at injector pump when engine stalls. I am also fairly certain it is not hydraulic stall now as both P1 and P2 pressure sensors show engine stall at 3600 psi and the high pressure setting is supposed to be at 5400psi. I am desperate now for any additional help.

 

[Kasper]

I had a very similar issue on a lbx lx240.check your engine condition, fueling, and pump regulator adjustments which will affect engine load on each pump

 

[steiger10]

Hello folks, I have a 2005 CX 240 that with any function kills the engine even at full throttle. Not a fuel issue as it has 14psi fuel pressure to stall. It’s like a load valve is stuck closed or something not letting the pump or pumps destroke. Has anyone delt with this before I start replacing parts? Thanks in advance.

I have 240 also doing the same thing put inj pump &new hyd pump didnot change