When the machine has been running for 20minutes the hydraulic movement and track movements become very slow. If machine is stopped for a couple of minutes and restarted the machine is ok then for a few minutes and then goes slow again. Can anyone help or suggest a solution?
this is a common problem with the hitachi's. your problem is either the displacement solenoids or the angle sensor. check out this thread there are also a couple of other good threads you just have to search for them.