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97 Komatsu PC300LC-6 Avant fuel shut off solenoid keeps shutting off.

Atokatim · 2024-06-05 10:52

Hello all! I have purchased a PC300-6 that has been running fine for the past couple months but recently decided it no longer wants to stay running. The engine will start and run for 1 second then immediately die. When manually holding open the fuel shut off arm, the machine runs perfectly fine. All the fuses under the display panel seem fine and there are no codes on the display. Whoever had it before me did some wiring hack jobs but I can't seem to find a wiring diagram for my machine to even begin tracing any issues. I just don't know where to start looking to fix this issue. Any help is greatly appreciated. Currently running the machine with a piece of bailing wire holding the fuel shut off open to get this customer job done.

Replies7
  1. #1BluewaterLa2024-06-05 10:56

    I would change that solenoid

  2. #2Atokatim2024-06-05 11:16

    It activates perfectly fine and does not appear weak at all. It appears as though the solenoid is instantly losing power within a second of the engine starting. I did not put a meter on it while I was out there...

  3. #3Atokatim2024-06-05 11:27

    Are there any specific things that could cause that solenoid to trip while running? It was running for 45 minutes to an hour and then all of a sudden shut off. Now it's no longer staying running after that.

  4. #4BluewaterLa2024-06-05 11:29

    Get a helper to start the machine while you check it with a meter, The wiring hacks could be an issue from poor connections

  5. #5BluewaterLa2024-06-05 11:33

    Sounds a lot like the solenoid is bad to me, there is not that much in that system on a B model. Solenoid is likely overheating quick and not working. Few times I've found corrosion under the ignition on the power tabs that can cause some issues, something easy to check and clean up quickly.

  6. #6thepumpguysc2024-06-05 20:57

    Is it a 2 or 3 wire solenoid.?? If it’s a 3 wire, there are 2 different windings inside.. A pull in coil and a run coil.. 1 or both could be bad or the relays that feed them could be bad.. Make sure ur getting the correct voltage.. (24v.?) Ur probably gonna need a wire diagram..

  7. #7Atokatim2024-06-15 13:58

    Solenoid replacement fixed that problem... Now I have another, but will start a new post for that one. Thank you all for the help