Hello, I am asking to some help regarding Hitachi EX120 machines, I am new to tracked excavators and have only driven and owned backhoe machines and have little experience with track machines. I understand that a USA spec may differ from UK spec but what should I be looking out for on these machines I understand about undercarriage wear and what not but havent got much basis for judging how worn slew rings etc are. I viewed a machine yesterday and there a very slight rock on the turntable which I could feel while operating, should I walk away from the machine, I'll try to attatch a picture, the machine is a 1996 EX 120 Any advice would be greatly appreciated Thanks Chris
Utah You don't mention how many hours are on the machine. If you can feel the play in the swing bearing it is really bad. Anything over 3.05mm of play is bad. To check the play in the bearing you need to attach a dial indicator with a magnetic base to the carbody with the indicator touching the outer part of the bearing bolted to the upperstructure. It takes two people, one operating machine and the other to read the gauge. It can be misleading judging the play by sitting in the seat and rocking the machine.
Rocking Turn Table Don't walk away, RUN!!!
They claim there is 5600 Hrs on this 96 machine, I know it is hard to judge the rocking but i would say there is more that 3mm of rocking I have had a look at the turn table while my father was rocking the machine and vice versa I think it would be best to leave it. Thanks for the reply
Hi there Johny, Im from N.Ireland to, im a plant fitter and wouldnt mind have a quick look for you if you d like?
Were you rocking it side to side or up and down by pushing the bucket into the ground. Up and down play on a new bearing is about 0.030 to 0.040 inch. Anything close to 0.100 inch up and down is junk.
not junk It all depends on your price, a worn swing bearing is not that big of a deal. A good tech can fix her up in no more than two days. But if you don't want to put money in her you best be walking. Just remember in about 95% of used machines like this, you will be buying something in the first 100hrs. There is no way around it, so just be aware.