Hi guys Just wondering about something. Later this week i have to service a 2012 hitachi 240zx-3 theres roughly 2500 hours on it and hitachi done the servicing up to 2000 hours. Since new the driver claims the machine hasnt been very gutsy not much digging power. At 1 of the services the hitachi technician told him that they are set well below limits when leaving the factory for warranty reasons and that the pumps can be turned up? Has anybody any experience of this? Would flow or pressure need to be increased? A relief valve somewhere or maybe on the head of the pumps? I dont want to touch it until i have some info as things like that are best left untouched if undure in my experience!! Cheers guys
Operators are always putting that rumor out. I've done PDIs on hundreds of machines from the factory and it is very rare to see one set low deliberately. The reliefs do take a set over time and should be adjusted back to factory specs. Generally it was common on Komatsu machines to run the reliefs at 2,500 hours and then they would stay for the next 5,000 or so hours. Hitachi machines didn't seem to be so apt to change that much. If you have a gauge set and know what you are doing it might be worth checking the system. If this is your first time you better get a hold of the dealer. High pressure oil is nothing you want make a mistake on. You can check the performance of the machine by running cycle times on the boom. Stretch everything out and set it on the ground. Put the engine at high idle and the machine in the fastest mode and time how fast the boom goes from the ground to the top of its stroke. It should be between four and five seconds. If you get that then tell your operator to go back to work.
There are a handful of things that could be out of whack here: -throttle not at 100% -pump speed sensor nfg -regulators set up wrong -reliefs set up wrong Pressures can be checked in the monitor if you know how to get into the service menu. FWIW, if you dont already know how to check these things, its probably best to not touch anything and have the dealer set it up (assuming they know what they're doing)
Cycle times are best checked by track speeds on the newer hitachi/deere hoes. Doing boom cycle times is scary at best on anything bigger than a mini. lol
Cheers for the replys guys. I operated the machine myself for a bit and it does seem gutless compared to the same size machine in a komatsu or volvo. Its not slow just gutless. Now that you say it it doesnt seem to rev up very high so that might be worth looking at
You can monitor the engine rpms operating pressures and just about every other funtion on the hoe from the gauge display. Everyone says that their new tier 3 isuzus aren't running up to speed but when you actually check them with the tach they're usually running the correct speed. I know when we got ours I thought something was wrong with the engine rpm. But checking it with the display it was spot on. Economy mode will run it at 1800 rpm and rev up when a hydraulic load is applied. 21-2200 rpm if memory serves me correct. Been about 6 months since I was into the display and actually looked. Ryan