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Cat 279c lost all hydraulic and fuse blown

svenb10 · 2025-11-04 11:57

randomly lost all hydraulics when scooping up dirt, checked fuses and hydraulic solenoid fuse was blown, replaced it and still not working. Does not drive or bucket lift. cab fuse box has 2 different hydraulic solenoid fuses where can i locate the solenoids for both fuses? Also when i put in a new fuse it does not blow but hydraulics still don’t work. Kinda lost here on where to start. any help is appreciated thank you.

Replies5
  1. #1Nige2025-11-04 12:59

    You’ll need 2 people for this. One in the cab, the other round the back looking into the engine compartment. Start the engine and have the second person observe the cooling fan located below the radiator. It should start to spin as soon as the engine fires up, maybe even during cranking. Does it.?

  2. #2svenb102025-11-04 13:08

    just tried this and the fan does not spin

  3. #3Nige2025-11-04 13:29

    The coupling between the engine and the hydraulic pumps has failed What's the machine Serial Number.? MBTxxxxx I imagine.

  4. #4svenb102025-11-04 14:00

    Ok that makes sense, i’ll dive into tearing the pump off. MBT00373

  5. #5Nige2025-11-04 17:24

    You might find the attached useful. The plastic coupling is referred to as a flange. Part Number 226-7635.