Kato HD 900 SEV slow operaion

[Mark250]

Hi all I need some help with a Kato HD 900SEV digger S/n 900514sw
the machine has pilot operated controls for the main attachments and uses cables to operate the travel spools
the problem is when machine warms up the functions on the left hand joystick go slow. operating the right hand joystick improves the slow functions. i suspect the pump signal system but do not know how it operates as the pilot lines go directly to the main control valve .there also appears to be no pilot pump as such.
As I am unfamiliar with Kato hydraulic systems I am hoping some one on the forum can help with either experience or manuals and schematics
Any help most appreciated

 

[Tones]

There are 2 pumps piggy backed, each pump supplying 1 control bank.Follow the hoses from the pumps to find out what goes where.As a starting point flow and pressure test the pumps. If they are ok then move onto the control bank and test.The problem could be as simple as a broken 0 ring at worst a worn pump.
Has this machine run a rockbreaker? If so check the quality of the hydraulic oil.I have experienced grease contaminated oil which came from using rockbreakers resulting in stuffed pumps

 

[rocknrabbit]

I may have a manual to suit you, I will have a look for it when I hear from you. Where in this fair state of ours are you?

 

[Mark250]

thanks rocknrabbit I am in ballarat