I just bought a 2012 Kobelco sk80cs-2 excavator. When tracking with the blade up off the ground the machine bigs down terribly when even moving the blade up or down in the air. Same goes for trying to move the boom while tracking. The spec sheet shows max rpms at 2200 but the machine will not even reach 1800rpms. Shouldn’t the machine reach max rpms? Shouldn’t I be able to work 2 different functions at once without it bogging down?
Any auxiliary switches on by accident?
Not that I can see. Shouldn’t the Rpms be more than 1780? I think it idles are around 1200.
Yes it should . What are the rpm when throttled up not working?
1780 max rpm without moving!
Does it have different work modes (fuel saver, standard ,heavy and so on)?
Not that I can find. It has a hydraulic thumb attached. There is also another valve on the side of the cab that has “hammer” written on one of the 2 valve positions. It is not turned on that position though. If the specs show my max hp at 2200rpms, shouldn’t it get close to reaching that?
You may have to go into menu to see if you have it.
Thanks for the quick responses! I’m not at the machine now so I was just trying to get as much info on things to check when I get back to it. You do agree that 1780 is way to low to max rpms though right?
Seams low to me , but with all the fuel saving and pollution crap they do today who knows. I would get an operators manual to see what controls what.
I used to have a Kobelco 70 and it did have work modes, Economy, slow and heavy (letters on the display E,S, and H I think) I believe they should be on the bottom of the consul screen, you push one of the buttons on the consul to switch modes. I’m pretty sure it would always default to “S” when the machine was shut off and restarted so you have to change modes every time, I’m pretty sure this would keep the rpms down.
Thanks I’ll check it out. Did yours seem to allow you to run different hydraulic functions(tracks/boom or blade) and not smoother down?
Even with all modes (power fuel saver etc.) You should be able to turn them all of and use manual throtle, or at least use power mode. If you can't reach 2200 then, even without loading it up, then you have some sort of fueling issue I'd say.
The machine definitely did not "smother down" when using functions. Like Roamer said, it sounds like a fuel issue. Have you changed the fuel filter and drained off any moisture in the fuel tank?
I shouldn’t have used “smother down” as the description. It more so just puts out half or less of the function you are doing when you try to do another one but the rpms aren’t really dropping. Say your tracking forward and try to lower the blade or work the boom at the same time. The track speed slows down and the blade or boom(whichever your working) moves at about half speed. If you stop one function the other immediately moves at full speed. I don’t really think it’s a fuel issue. Again, thanks for the replies and trying to help me get it trouble shot
First of all, you bought excavator with a problem I assume? Try to get as much info from the previous owner if possible. They might say that it never reached 2200 but didn't have problem with bogging down, or that RPM and bogging started happening at the same time. That will help you a lot in your further diagnostic process. If you can't find out any history, I'd start from the ground up. Try to get your RPM sorted out first if you are sure that it needs to hit 2200. Without healthy engine who knows what sort of problems it may create. Again, not reaching max rpm is a problem in it self, regardless of this other issue. Is it a double pump split between tracks and boom / blade / bucket etc.? if so, if both tracks slow down, not just one, I'd say something in your control circuitry doesn't like what is happening. If you have flow problem, then one track would slow down more than the other. Unless there is some sort of equailizing circuit for tacks speed. I don't know that model at all, so I'm just trhowing out general ideas.
How many hours does the machine have on it?
That is how the machine will work the tracks take flow from both pumps so anytime you move ANY other function it slows down. The machine has 3 modes H S & FC in you should have 2250 rpm in H mode 2100 in S mode and ONLY 1800 in FC. The bigger machines also have a mode where it splits the functions and allows you to track and use the other functions at the same time. But there again what it does is use one pump for travel and one for the other function so you will be slower with everything to start with.