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  1. T

    Komatsu pc490-10 slow boom up

    We checked ours and the initial issue followed the sticks ruling out the pattern valve. I am supposed to be on that job site tomorrow and if everything works out I am going to put the quick dump valve on.
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    Komatsu pc490-10 slow boom up

    We never fixed ours. Komatsu came out and has suggested we replace the quick dump valve for the stick circuit on the control valve. Parts showed up but no time to sort it out. They recommended this replacement because they were seeing pilot pressure on both sides of the stick pilot . I.e. when...
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    Komatsu pc490-10 slow boom up

    I will check in the am. Thanks for your help.
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    Komatsu pc490-10 slow boom up

    I did not. Does it have a specific callout in the menu or does it need to be checked on the control valve? I’m unsure of the location..
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    Komatsu pc490-10 slow boom up

    This is in p mode. I also thought this was on the low side but I am more familiar with Deere where they run around 550. What led me away from pilot pressure issues was it functioning normally with the same amount of pilot pressure. I should have noted it will do this more often with a full...
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    Komatsu pc490-10 slow boom up

    We have a pc490-10 and occasionally the boom will raise slow. Some other function like stick out and slew seem to also be slow. It is very random. What we are seeing is the rear pump not increase displacement. It sits at 24cc while the front pump will go to 206cc. When the boom functions...
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    Cat 336 delayed response

    recently made it back out to this machine for some other repairs but need to circle back to this... If it still runs it can't be that bad... Tried the accumulator test while on site. Didn't have any gauges but the boom does not come down with the machine off. Tried it on another one at the...
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    Cat D8N Transmission issues

    Do you have a part number for the power trains oil cooler? The dealer has sent a few but said the machine is too old and sis is not specific on what it is... I think the rad core is 7E-9595 1W-0289 was the first cooler picture they sent. I think this matches the cooler between the engine and...
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    Cat D8N Transmission issues

    We have been having some issues with the trans heating up while pushing. It also feels a little weak. Recently noticed a very small amount of sludge around the dipstick. Somewhat like coolant is the trans. We also noticed the same in the radiator but much worse. Is it possible for coolant...
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    Hitachi zx350-5

    Does anyone have a source for the hitachi to Isuzu code conversions like posted above?
  11. T

    Hitachi zx350-5

    We are now getting codes: 81-00 108-04 10026-15 The previous codes seemed to have resolved themselves when I went out to check on it... what about a bad engine harness?
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    Hitachi zx350-5

    Great thanks for the information. This is very frustrating. It seems like this is either a bad MAF or alternator. I'm not sure how the MAF would do this but...
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    Hitachi zx350-5

    Looking for help with codes. 10012-02 10026-15 Machine does not want to regen. Seems like it is mostly related to code 10012-02 as that one has been coming up intermittently. Hoping someone can point me in the right direction as this is our only hitachi and we don’t have the software to...
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    Cat 336 delayed response

    Is anyone able to supply a hydraulic diagram so we can check for the filter?
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    Cat 336 delayed response

    I will have to get a look at the machine later this week. But I thought all the controls on the f series were electric pilot?
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    Cat 336 delayed response

    I think that machine does have a pattern changer. But the controls are electric over hydraulic. So no pilot lines in the cab.
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    Cat 336 delayed response

    I thought these controls were electric over hydraulic? I'm would assume there is still a pilot system but it is controlled by solenoids not the joysticks directly?
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    Cat 336 delayed response

    Any suggestions? This is driving me crazy
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    Cat 336 delayed response

    Do you have a repair or inspection procedure available?
  20. T

    Cat 336 delayed response

    Cat 335fl Rkb10639 When using the controls it seems like the hydraulics have a delayed response. It is the same when letting go of the joystick. The machine takes about 1 or 2 seconds to stop functioning. it makes it very difficult for delicate work. For example if I pull the control back to...
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