Kx121-2 hydraulic relief help

[Rollonzo121]

This is on a kx121-2

When I try to lift boom, curl bucket or use right track under load It feels like the hydraulics slam shut. It's not the same feeling as say when I stick out untill it pressure relieves and hold it. It's very abrupt. It works for a fraction of a second the loses pressure abruptly.

If I activate stick out or in a bit and use boom, curl or right track they work at low pressure I believe they are just sapping the left side of control valve or something like that. I'm not sure but I can still dig because I naturally run the stick a bit when I boom lift. It works decent if it's not reaching out. But if you are reaching far out and there is a bigger load on the boom cylinder because of the weight it barely works even with the stick.

The control valve has 2 sides and I have swapped the relief valves under the 2 main feeds. No change right side still pressure relieves.

Are there relief valves I am missing for that right side? It's a dual action piston pump system so one pump but acting as 2. Only one side has this problem.

Thanks much

 

[whitetiger]

First, you need to provide the full model number of your excavator, not just part of it.
There are five different variations of the KX121; some have three pumps, others have fewer.
A "dual action piston pump" is not on any of them.

 

[Rollonzo121]

Kubota kx121-2, it's the first sentence of the post. As far as a serial number I can't find one on it.

 

[North Idaho Wolfman]

Kubota kx121-2, it's the first sentence of the post. As far as a serial number I can't find one on it.

2 points and the second is real important:

You know we can see that you edited the thread 4 times.

Getting short with the one person that really knows these units better than any of us, not a smart move.