lack of pover zetor

hi anyone ,calling from norway.just resiliently i got a zetor 7540.hawing problems on the diesel side.the tractor feels very week ,lack of power up hills.have changed all filters ,no respond. may bee foul thy regulator,worn out pump,cant find any leeks on the system.anyone who has been having the same problem? feel free to answer.best regards KNUTEN

I would get the injector pump checked out. It may need to be opened up a few notchs. I know a man who had a John deere with the same problem as your 7540 and the problem was cured by adjusting the pump. Get a qualified experienced engineer to do the job. Best of luck with it.