I have a 1987 mitsubishi ms120 excavator with a turn drive problem. when I start or stop turning the machine shakes. I checked the bearing and it seems still good. I changed the oil in the gear box and it still does the same thing. It seems like the swing bkake is hangin up. I just bought this machine and it has been sitting for over a year with a starter problem. Can anyone help me???
kawasaki mx80 drive is anyone familiar with this turn drive motor. I believe the problem is in the motor and not the gearbox or bearing. The more delicately I move the stick the more the machine shimmies. full speed movement is ok, just fine movements seem to be rough
I found the problem 2 years later and almost 300 hours. used the machine one day and while swinging around I heard a clunk. next the machine wouldn't stop spinning to the right. I pulled metal chunks from the spool and then removed the swing motor. inside 3 pistons in a row were wiped out and one top end broke off. the 3 in a row were worn down and flopping around. I replaced the rotating assembly and all my problems that it had swinging are corrected. smooth swinging with no shakes and when I let go of the stick the machine stops and not shake. found parts at http://www.hydraulicpartssupply.com/
I just bought a 86 MS120-8 with what seems to be the same issue. Thanks for taking the time for posting your solution. -Van
If you don't mind, I would like to get the chance to talk to you about this machine. Though I have a strong mechanical background, I have never worked on heavy machinery and could use any pointers that you might have as you have worked on yours. I have also tried finding service manual for it and have been unsuccessful. Is the design of this machine similar to another that a manual is easier to acquire? Thanks for any help. -Van