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Kobelco sk120 MKv

Discussion in 'Excavators' started by aussie-farmer, Feb 15, 2007.

  1. aussie-farmer

    aussie-farmer Member

    Joined:
    Feb 14, 2007
    Messages:
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    Location:
    australia
    Hi all,
    I am new to the world of excavators and this site. Lots of wheel tractor experience - nil with earthmoving !
    About 10 months ago I bought a 1996 SK120 Mk v (2500 hours),for general farm drainage,dam cleaning,stump removal etc.
    So far have had no sign of any major problems (apart from starving for fuel that a filter change seems to have fixed - wouldnt rev up past 6 notch on dial - now goes to full - will keep my eye on it as it may have crap in the fuel tank or lines). I had it independantly checked by a guy who does these inspections for a living in the mining industry and he did mine in the dealers yard.took about 5 hours to go over the machine , check oils, test drive etc.
    I was told it was about 90 - 95 % in every way for a unit with these hours.

    What I wanted to know was if there is any kobelco or Sk120 model,inherent problems I should watch for or expect.

    I would also like your thoughts generally on Kobelco and this model, a few local contractors have bigger kobelco diggers and like them.
    A mate of mine has a Hyundai 13 ton and wouldnt swap it for anything.

    Intereted to know your thoughts.
    AUSSIE FARMER.
     
  2. Countryboy

    Countryboy Senior Member

    Joined:
    Jun 8, 2006
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    Occupation:
    Load Out Tech. / Heavy Equipment Operator / Locomo
    Location:
    Georgia
    As I'm not familiar with your machine, I can't offer any advice. Welcome to HEF though. :drinkup

    What kind of crops are you growing over there? Pics of your equipment are always welcome too. :yup
     
  3. tylermckee

    tylermckee Senior Member

    Joined:
    Jan 9, 2006
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    Location:
    washington
    Sounds like you got a pretty nice machine, well taken care of. I dont know of any inherent problems with that machine, i know people that have/had similar machines and they all seem to hold up well. I've ran a few kobelco machines around the same year and thought they were a decent machine. My boss used to run all kobelco excavators at the last place he worked and he loved them. Now we run all hyundai and we cant complain, IMO better than any hitachi/deere i have ran.
     
  4. DurtyMurty

    DurtyMurty New Member

    Joined:
    Mar 4, 2007
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    Location:
    Ireland
    Thats pretty well my introduction as well - 6 months ago - general farm use- 98 sk100 4000hrs - including the fuel problem - not the main filter but a little mesh filter under one of the banjo bolts before the main filter.

    When buying, I was advised that the two most common faults on this machine are

    1 the lcd dispaly panel - costs about 1000 euro - (even more in dollars) in this part of the world. It's a simple lcd display - should cost about 100 but it's custom made for kobelco and now obsolete, so I guess that's what we have to pay kobelco for keeping a stock of these

    2. Your stepper motor problem. I was told it's usually an ECU problem - That costs aboot 2500 here so on older machines many of the guys just disconnect the linkage and fit a manual throttle cable. You lose the auto throttle fuel saving feature, but you'ld never save the 2500 anyway. Like you. I'm very new to this and am not speaking from experience but, in another life, I have a bit of electronics experience and would guess there are some driver chips for the stepper motor that are failing on the ECU.

    Keep in touch on the motor and happy diggin'
     
  5. Squizzy246B

    Squizzy246B Administrator

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    Occupation:
    Digger Driver
    Location:
    Perth, Western Australia
    Hey Durty(Murphy?)Murty. Welcome to the forums...great post, good info.:thumbsup
     
  6. aussie-farmer

    aussie-farmer Member

    Joined:
    Feb 14, 2007
    Messages:
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    Location:
    australia
    Hi all,

    Thanks for the advice Durty ,due to have the sk120 serviced anytime now. Hasnt done it again lately, but will certainly will get it looked at. Where abouts in the fuel line, are the Banjo bolts you mentioned that had the filter ?

    Thanks for the info you added also!

    cheers.
     
  7. d4c24a

    d4c24a Senior Member

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    Location:
    ENGLAND U.K
    banjo bolts

     
  8. tylermckee

    tylermckee Senior Member

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    Location:
    washington
     
  9. Mari

    Mari New Member

    Joined:
    Jul 7, 2008
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    Location:
    Finland
    Hi,

    First of all, I'm very sorry to post my question to this old thread, but I'm new and I just may post replies today. This was also the nearest thread to my item...

    Does anyone know is there user manual available in the internet for Kobelco SK120? I can find parts catalog, but it may not be enough today.. Guy's are trying to find answer to hydraulic problem from Kobelco and woman from internet :eek: :p . 300m of small road is waiting to be done here - and I need to translate everything to the guys.. Anyway, user manual would be very usefull in the future also.

    Parts catalog I found from http://www.kobelcoamerica.com/

    And if someone is interested, more specific information of "our" Kobelco:
    SK120LC Mark 3, YP-02094, year 1993
    Been here about 2 months..
     
  10. d4c24a

    d4c24a Senior Member

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    Location:
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    whats wrong

    if you post what the problem is someone on here may be able to help :cool:
    its full of great minds and a few odd ones :D and one pain in the butt :D:D
    :drinkup graham
     
  11. MKTEF

    MKTEF Senior Member

    Joined:
    Apr 5, 2007
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    1,008
    Occupation:
    Production manager
    Location:
    Norway
    Hello Mari!

    If u try to explain for us the problem your guys got, i am shure some here can help u.:)
    If u open your account for private messages(PM) u can even get som info directly.
    And i bet we can do some discussion in swedish...Via a PM.

    A Kobelco from 1993 may have a lot of hours on it, i know from past experience that old Kobelcos often get hydraulicpump problems.
    A estimate of how many hours the machine has been doing is also usefull info.

    Post some more posts and u get more priviliges here on the forum.:)
     
  12. Mari

    Mari New Member

    Joined:
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    Location:
    Finland
    :D Great ideas ;) I just did have a few problems here.. First, I do not know the specific english or swedish words of this (technical) area and I need to translate many of those with some dictionary. Second, the guys was not here ;)

    But now I can try :angel :
    1) They wanted to know where to measure hydraulic pressure
    2) This excavator have had grab/clamshell bucket/jaw crab (http://www.koneosapalvelu.com/main/images/stories/tuotteet/vahva.jpg) for timber work. For that there seems to be done some change to hydraulic. Now Kobelco does have "acclivity scoop" (http://www.ahirvonenoy.net/kallistusluiska.jpg). When "acclivity hydraulic" is active/set ON, power loss is notified in digging force/power. When "acclivity hydraulic" is set off, the digging force and speed become back to normal. This "acclivity hydraulic" is set on/off from electric button on top of the "push plates control stick" :falldownlaugh ("push plate" = http://image.nettix.fi/extra/machineimg/635701_635800/635749_e7e9e96e102c4bb2.jpg). Might be that normally from that button the speed should be set to low/high (slow/fast). When "acclivity hydraulic" is set on, also the "push plate" is working. When this button is pressed again, "acclivity hydraulic" and "push plate" does not work at all. This practically means that the "acclivity hydraulic" cannot be used while digging... So, what is wrong? Why "acclivity hydraulic" makes Kobelco to loose digging force? Previous owner did not have answer..

    Still, we do not have user manual at all, so it would be also nice to find ;) - even in english :duh

    I have written this too long time... First tried to understand the issue in finnish, then to find english words near enough :dizzy and then I need to understand your next answers ;). So please, help my work by defining first correct words for mine, so I can folow. E.g.
    grab/clamshell bucket/jaw crab =
    "acclivity scoop" =
    "acclivity hydraulic" =
    digging force/power =
    "push plate" =
    "control stick" =
    electronic button in "push plates control stick" =

    MKTEF, Thanks for the offer, but after all, I think the english is still better language for me :eek:

    One remembered (?) that usage hours have been 8350.
     
  13. MR. KOBELCO

    MR. KOBELCO Resigned

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    Occupation:
    PARTS & SERVICE MGR. AMOUNG OTHER HATS @ KOBELCO D
    Location:
    CANADA
    if your current driving the stepper motor gets too high the computer will turn off the power driving the motor in order to protect itself.
    common problem with stepper motors that are nearing failure.
    the grease inside breaks down or being worn out too much play in the shaft and the gears start to pile/lock up on themselves.
    also the ball joints might be worn out or packed up with dirt.
    both the ball joints and s/m need to be free for movement.
    note: whatever, you do never pull/yank, etc... on the rod of the stepper motor when the power is on by the key.
    if you do you will definitely need a computer.
    the setups of the stepper motor needs to be properly mapped with the computer - a dealer specific "A" adjustment, depending on machoine it might have an optional "B" adjustment.
    i would probably buy two new ball joints as well as the linkage bushings (inserts) and/or linkage if worn and contains no bushing and change those first.
    when you change do not remove totally.
    remove only one end at a time.
    you do not want to disturb its' positioning in reference with the s/m.
    or else you will also need an "A" adj.
    in that case call a dealer.
    if no dealer is in your servicable area i may e-mail a procedure but i require your serial number first.
     
  14. aussie-farmer

    aussie-farmer Member

    Joined:
    Feb 14, 2007
    Messages:
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    Location:
    australia
    Hi guys,

    Long time between visits !
    Machine update, going well with around 3000 hours now. not a lot of work, hasnt stopped raining since we bought it, so no dams cleaned yet.
    Fuel issue is sorted for now, cleaned tank of rust flakes and basically the whole line fron tank to the banjo bolt was chocked. Lots more power and performance.

    The warning still appears occassionally with no drop in performance etc, " STEPPER MOTOR NG" and after reading the Aug 08 Mr Kobelco post , sounds like it is a "Stepper Motor Needs Grease" reminder ????

    Anyone with a thought on that.

    I will get some pictures and post of the unit, my absence was largely due to outdated computer and being rural, no Broadband and whoafull dialup. Well, my hair is starting to grow back since updating and hope this finds you all well. I was amazed i remebered my password for here after all this time.

    Cheers for now.
     
  15. MR. KOBELCO

    MR. KOBELCO Resigned

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    PARTS & SERVICE MGR. AMOUNG OTHER HATS @ KOBELCO D
    Location:
    CANADA
    the stepper motor cannot be opened and greased.
    to fine a component.
    with the key off, unit powered off by the battery disconnect relay.
    check the play in the stepper motor shaft if excessive its worn our.
    should really have no play.
    if you want to try first lubricate the ball joints on the rod ends well.
    if has no ball joints replace the pins, replacable bushings in each linkage and r-clips one at a time as not to put the stepper motor out of its' position. worn pins/bushings can jam up causing this code to show on the display.
     
  16. mireland

    mireland New Member

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    Apr 20, 2010
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    Location:
    ireland
    sk120 mark v pump control problem

    hi i have a sk120 mark v with helicopter cab, the problem i have is the controller is not upstroking pump1 so my bucket and right track are slow. i ran new wires from the controller to the pump and no change, the controller is not sending out a signal to the pump to upstroke it. i fitted te controller in another machine and it worked fine. the guage cluster screen is not working but there is no alarm sounding when the machine is working. any help greatly appreciated.
     
  17. MR. KOBELCO

    MR. KOBELCO Resigned

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    Location:
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    mireland
    re: sk120-5
    to help me help you please take digital pictures of your cab display, cab switches as right and left hand consoles, the hyd pump in the compartment and the computers etc... stationed under the console behind the cab seat.
    in regards to your display, has the display just quit or have you looked into why it is not working?
    reason being is that kobelco's service maintenance screens are accessable by the display and it would be a huge help to view.
    my e-mail: hf_hydraulics@hotmail.com