Hello I have a 1995 Hitachi EX100-3 and when cold works great, but after 20 minutes of usage it begins to lose hydraulic power and the hydraulic oil becomes very hot. All functions become very slow especially the tracks. I think it may be one of the pressure relief valves. Any suggestions out there? Thanks
most likely its the main pump bypassing when the oil get thin when hot .....i had the same problem with my screen plant i replace the pump and now its fine and that was over a year ago
Yup, get a Deere or Hitachi tech to do flow and pressure checks, give you the bill and the diagnosis. They have the tools and the specs, might save you a bundle and a bunch of headaches in the long run. Mind you YMMV dealer to dealer......