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Recent content by TexasDan

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    Komatsu PC78 MR6 low power and stalling

    I'm gonna be working for the next 24-48 hours, but I'll try to get back out to the machine as quick as I can and test this. I talked to a mechanic over the phone and they were thinking it could be a "pump merge valve", I'm gonna do some more research on this and see if there are any diagnostic...
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    Komatsu PC78 MR6 low power and stalling

    Is it the same with your machine, in that, it gets worse after you track somewhere, but if you're just digging in one place it will work fine? Also, is supply pump the same thing as the primer pump?
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    Komatsu PC78 MR6 low power and stalling

    Sorry man. I'm trying my best to explain what was explained to me by the mechanics that worked on the machine. Essentially the pressure was monitored immediately prior to the injector pump, and the mechanics told me the replaced part of the pump that bolts into the injector pump, I guess I got...
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    Komatsu PC78 MR6 low power and stalling

    When we monitored the pressure we had a gauge hooked up between the fuel filter and hand pump.
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    Komatsu PC78 MR6 low power and stalling

    I'll try to get out there in the next two days to take a picture
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    Komatsu PC78 MR6 low power and stalling

    The hand primer pump was just replaced, that was the last repair that the shop tried. But when we we had gauges hooked up to the fuel system there wasn't a drop of pressure before the stall, but there was a gradual drop of pressure after the stall. Next time I get out there I'll check that...
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    Komatsu PC78 MR6 low power and stalling

    I've never personally messed with gauges on the hydraulic circuits, so a couple of dumb questions... Anything I need to know about disconnecting hydraulic connections? Do you need to de-pressure the hydraulic system before uncoupling the connections? Do you need to bleed the system after...
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    Komatsu PC78 MR6 low power and stalling

    Interesting, but if that was the case wouldn't it be pretty strong while traveling? It seems like it's almost never strong traveling, it will struggle, and occasional stall when tracking up a 1 degree incline. It also will barely counter track. If im going uphill and I want to turn to the left...
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    Komatsu PC78 MR6 low power and stalling

    They said they tested everything, but I don't believe it.
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    Komatsu PC78 MR6 low power and stalling

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    Komatsu PC78 MR6 low power and stalling

    Its not my style to dispute payments, but I tried to offer any other arrangement of renting out equipment, or getting mechanics to come out and look at it again, but their opinion was they spent so much time on the machine that they were actually giving me a deal. So essentially, they're not...
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    Komatsu PC78 MR6 low power and stalling

    I agree, im just concerned about bringing it back when they clearly have no problem charging a lot of money to not actually fix the machine. Im gonna get another guy from Kirby Smith to come look at it. I talked to another mechanic and he told me it may be the pump merge valve, pressure...
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    Komatsu PC78 MR6 low power and stalling

    I make try to get out the machine today and take pictures. if you see this in time message me your number and I can send pics to you
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    Komatsu PC78 MR6 low power and stalling

    CapnDean, Sorry I had to punt it to a service center cause it was getting over my head, essentially what they did was: Isolated the fuel system to see if the error could be recreated. The hooked up a 2 gal tank to a hand pump to the primer pump, just prior to the injection pump. The issue...
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    Komatsu PC78 MR6 low power and stalling

    I cant be sure off the engine right now before checking it physically, but based on the manual that came with the machine it's a komatsu 4D95LE-3-A
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