Volvo EW180C issues with arm and bucket not having power

[pados1002]

Hey guys, i just bought an EW180C volvo from 2008. First thing i did was to send the machinery in Volvo dealer for a big service and a control pattern change kit, because i wanted the backhoe pattern as well. The dealer checked pressures and they were in spec. Today, first day of having the chance to test the excavator, i found out that the arm cylinder has not enough power to either push or pull function. Same happens to the bucket. It will function up to a point where the load increases and then it stops. However the weird thing is that neither of the 2 make the pump or the engine bog or make them work hard. Feels like when it hits a certain load instead of keep pushing it just disengages the pump or some kind of pressure relief. What i mean is that i expect from an excavator, to be able for example, to grab with the bucket on solid ground and pull it self from a muddy terrain with the arm. At least the old O&K did that with ease. I 'll contact the dealer of course but something 's going on here. Same happens to both backhoe and excavator pattern.

 

[funwithfuel]

It sounds like a bit of debris might have found it's way into the pilot manifold. Are you sure you're fully engaged in either ISO or backhoe. It's very easy to mistake it.

 

[pados1002]

Thanks for the quick reply! I m pretty sure about that because i push it hard enough and the pin also locks properly so i gues it 's pretty unlikely. About the debris however, what 's the possibility of both arm and bucket spools being clogged? Hydraulic fluid was also changed in the maintenance.

 

[funwithfuel]

All pilot controls feed from common source, so yes, everything would be weak but travel and dozer blade

 

[pados1002]

Hm... Boom and swing however seems to load the pump and engine properly.
One more thing, that however i have no clue if plays a role, is that on pattern swap valve the 2 sensors are not connected anywhere.

 

[funwithfuel]

Those sensors tell the VECU what control pattern you're in. They're not plugged in? That's a bit of a problem. The machine doesn't know when to stroke or destroyed the pump.

 

[pados1002]

So do you believe that this can affect the function of arm and boom?

 

[Ben Witter]

The sensors on the pattern change are primarily there as an indicator which control pattern it is in. There should be connectors somewhere that would allow them to plug in, but you may have to change some parameters or change programming in the machine for them to function. That still should not cause individual functions to misbehave.

I would say you will need to check cycle times and working and LS pressure for each function and in both directions before you can determine what is faulty.

The pattern change valve could affect the function of the arm and boom if it were installed incorrectly or it is faulty. Did the machine function properly or the same before the valve was installed?

 

[pados1002]

Unfortunately the moment the machine was imported was also sent to the dealer service. We did not do any operational work to test the functionality. But the pattern change kit was installed brand new from the dealer.

One more thing (not related to the functionality): Any idea where the back up beeper should be located, if there was any and if you know the part number? Today I had an inspector to check the machine in order to proceed with the papers and he asked me to reverse and obviously no beeper.

 

[funwithfuel]

Those sensors tell the VECU what control pattern you're in. They're not plugged in? That's a bit of a problem. The machine doesn't know when to stroke or destroyed the pump.

That should have read "destroked" vs destroyed. I apologize for any confusion this may have caused.
Had any luck measuring pressures and recording cycle times?

 

[pados1002]

Not yet unfortunately. As I said pressures was tested before installing the pattern change kit and were in spec. After that I think they did not check again...

 

[pados1002]

Guys for you who may know... I m thinking an other solution instead of repairing or trying to repair my spool and housing. What if I take a slice and attach that to the Mcv like the other functions are attached, for example the 2-piece boom. And reroute all the hoses there. Do you think that this can work? Just some thoughts.

 

[funwithfuel]

You probably have an auxiliary function unused. To run hammer or shear. You could repurpose that bank, just know , you won't have fine control, that spool does not have extended lead in cuts that promote feathering and grading. It's more of an "open-close" spool. Any fine control will be dictated by the RCV inputs.

 

[Ben Witter]

You really need to get someone to work on the machine that has an idea what they are doing. You need to check working and LS pressure while using each function in both directions. You state that the dealer said it was in spec. What is the number the dealer measured as "in spec" is not a value.

There should be no need to try cobbling this machine to work nor would I try that.

 

[pados1002]

I have booked an appointment with their service again, for testing from them. I hope I will have a better idea...