I have at Kobelco excavator model SK210LC-6E (YQ 08 SERIE) does not turn off with the key switch. when I turn off with the emergency button the message "IGR pre heat" appear in the monitor
You should take a photo of your machine's monitor when your machine reports an error so that we can better understand what is wrong with your device
This is what is happening: 1. The excavator does not turn off with the key, I have to turn it off through the emergency shutdown button, then the message that appears in the photo appears on the screen. 2. then I have to disconnect the battery because if not, the message is not deleted and it keeps beeping. 3. When I disconnect the battery, the battery relay is heard disconnecting. Thank you for your assistance
Ok, most of the time this is due to a stepper motor issue. What we have found usually is that the stepper motor drive shaft splines have worn down and even a skip of 1 or 2 splines can cause the problem. So you might have to replace the stepper motor. Else if you fancy it, you can take it apart and and offset the driveshaft or turn it around so that an undamaged area is in contact. The reason is that the same area is in use and wears down the splines. You will have to do a stepper motor calibration (Adjustment A and B) afterwards.
just a small check: when you turn off the engine does it seem like the RPMS drop but just not enough to shut down the engine? If that's the case then its the above issue I explained. The stepper motor basically pulls the throttle lever to the engine stop position and then returns to the idle position when you turn off the key. But if the splines are damaged what happens is that it doesn't really go to the stop position so the engine stays on while teh electronics are turned off with the key.
Thank you Digger_hunter, that is not my case, when I turn off the excavator the RPMS are still high
Have a look at the stepper motor and governor levers. When you turn off the machine the governor winds back up the engine stop position and the stays there for a tiny bit and returns to engine low idle position. Have a look to see if it’s doing that first and you could probably see if theirs any slippage. Could be the splines are totally broken or the governor lever could be loose or some other issue with this.
Do as digger hunter said and also check the ball joints on the linkage arm if these are starting to seize up they can cause all sorts of problems with the motor. The best information you could give us is when the key is turned off what does the stepper motor do?. Does it do nothing, does it move towards stop position and then jump away?