Kobelco sk135 psv problem?

[svadilfari]

Hello
I have kobelco 135 which I recently bought from Ireland. It was said in good condition but as one of my friend said, it went in the wrong ship, it should have gone to Nigeria.
But anyways here it is. I have sorted some of the problems like worn out rollers and broken hydraulic fluid cooler but one problem gets me frustrated.

1. There are no error codes
2. The swing, dipper and left track are slow.
3.If I am swinging and pull the dipper little bit the swinging goes on full speed and vice versa. If I do more than one move simultaniously it works as normal.
4. I swapped the psv spools and the problems follows. Bucket and right track became sliw. Ordered new spool.
5. Yesterday it arrives and I change it in for the spool I had assumed was broken but no change.
6. I swapped the spools again and everything worked for 2 minutes, then the new (inner) spool started to degrade until everything was as it was before. So the problem followed again. Now the swing, dipper and left track are slow if I'm not doing 2 movements simultaniously.

I have yet to try swapping the spool I assumed was broken for the spool I assumed was good and see if then nothing works.
I have yet to ohm measure all the spools.
Is there some valve that opens between the pumps if doing 2 movements simultaniously or does the psv get stronger signal or bypass pressure sensor?

Hope someone has seen this before.
Best regards

 

[KOBE STEEL]

Hello
The functions you mention that are slow are all linked to the rear pump. Are you able to install pressure test points onto the pump regulators and read its PSV Signal outputs ?. You can read all the low pressure and high pressure sensors from the machines monitor if it is working, so go into the monitor and check your sensor and psv output reading. For example, go to screen display number 14 and check what pump 1 and pump 2 standby pressures are during low and high engine speed with no load/operation.