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  1. M

    What is Optimum Operating Speed for Excavator?

    Hi swampdog, you said that you have an EX270LC if that is the case there is no computer that controls the pumps. There is only a computer for the auto idle system and the work modes . The modes is the three position dial switch that you select either L,E,P. [ light, economy, power] the decal is...
  2. M

    EX120-2 auto throttle

    There is a master button on the switch panel where the key is. it should be the button on the left side of the auto warm up button. I am not aware of it being optional.
  3. M

    EX400LC-3 Ignition problem

    You are right, the diode is in the alternator. The alt. will charge ok but when you shut of the engine if the diode leaks the load dump relay stays energized and keeps the battery disconnect connected.
  4. M

    hitachi ex-120-2

    There is a gauge on the dash as well as a light. When the light comes on and the buzzer sounds where does the needle on the gauge point. They each have there own sending unit and harness.
  5. M

    Hitachi EX60 URG need electrical diagram

    If your unit is the same as the larger Hitachi I believe you are describing what they call a safety relay. It prevents the starter from engaging if the engine is already running. Also it disconnects the starter once the engine starts. It does this by a signal from the alternator. The regulator...
  6. M

    Kobelco SK300LC Series 4 Engine Bog???

    Disconnect the throttle linkage that Koby is using and wire the fuel lever to full and give it a try. If that won't work then look at hydraulic pump control.
  7. M

    Kobelco SK300LC Series 4 Engine Bog???

    Trucks use a variable speed governor that allows the driver to adjust the amount of fuel being delivered to the nozzles. A variable speed only governs fuel at idle and cuts back on fuel when the RPM reaches the set maximum for that engine. It will add more fuel to maintain max RPM if the...
  8. M

    jcb js130 throttle prob

    Not being familiar with JCB. I would suggest turning off the auto idle system. If you do have a fuel pressure gauge to install after the secondary fuel filter install it and observe the transfer pump pressure while digging. If the engine speed starts dropping and the fuel pressure is dropping...
  9. M

    Kobelco SK300LC Series 4 Engine Bog???

    Do you know if it operated ok before the engine swap? I have found with engine swaps that sometimes the engine installed came out of a truck. Trucks use a different governors than excavators.
  10. M

    EX400LC-3 Hydraulic problem

    I have a conflict between the book and the wire diagram. according to the book #7 fuse is protecting the PVC. The schematic has it going to the monitor controller.
  11. M

    EX400LC-3 Hydraulic problem

    And after time if the fuses haven't not failed connect the 2 pressure sensors. There is one other 5v sensor in the throttle to keep in mind. Verify your suspicions until you are completely convinced you have the proper sensor before you buy new. I am not sure but I don't see why the #7 fuse...
  12. M

    EX400LC-3 Hydraulic problem

    From the picture the bottom row if it box were installed looks like the left side row with 2 1A fuses closest to you. after them they should read 5A then 2 more 1A fuses then a 5A then a 1A that had failed. Then the next 3 fuses should be 10A. The fuses in the picture do not appear to be in the...
  13. M

    EX400LC-3 Hydraulic problem

    It is possible to have bad connections, also check under fuse box for corroded joints and wire terminals. Make absolutely positive that water from the A/C can not drip onto control units. Cover them with something that will shed water.
  14. M

    EX60URG Tracking problem

    I have checked with many seal supply outlets and haven't found one yet that have the high pressure seals. If they are available other than the dealer let us know were.
  15. M

    EX400LC-3 Hydraulic problem

    Cutting Edge is right. Even with out the C/W device the harness is there and a problem in it will de-stroke one pump. If the wires on the pump solenoids can move or are dangling the wires at the solenoids can break inside the insulation. Check them with an ohm meter. If they check out then...
  16. M

    EX400LC-3 Hydraulic problem

    The 2 controllers are under cover that looks like a tray behind the seat. The PVC is the larger unit on the bottom. the top unit is the throttle or EC. They each have a red LEC (light emitting diode) . They both should have a slow steady pulse. You will find if you cover one while observing the...
  17. M

    Daewoo Solar 55

    If the motor is driving the sun gear directly you probably could. But you may be knocking on a thrust surface or ball bearing. It is best to knock as close to the stuck area as possible. You likely have cast iron covers. If you remove the cover for the return filter you probably won't drain...
  18. M

    Daewoo Solar 55

    I am not familiar with your make of excavator, but if there are threaded holes around the rim of the cover that you can run a bolt in to pull the cover or use a slide hammer. Try not to distort the cover if you need to use it again.
  19. M

    John Deere 490D problem

    If you are confident that there is no pressure on the 5000 gauge when the oil is still hot install a 1500 PSI and see what the circulating pressure is at full RPM and the safety pilot shut off in the working position. Remember not to touch any functions or your 1500 gauge will become stressed...
  20. M

    John Deere 490D problem

    Your pilot pressure, 700 PSI is ok. The specs. for main pump over relief is 5000 PSI. The surge relief pressure and line relief pressure should be about 250 PSI higher than the main relief. The pulsing in the pilot system is likely the pump solenoids maintaining the pump displacement to what...
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