Heavy Equipment Forums Heavy Equipment Community

d3g hystat problem

sam123abc ยท 2020-03-22 01:47

Hello . I have a d3g 2004 serial d3gkcxt00456 ( but the caterpillar system wont recognize it so i use byr00456 - ) I had the park brake come on suddenly and it wouldnt move and there was no transmission light come on the dash so no fault was recorded . so i checked the p switch - it was ok . I checked fuses - all ok . voltage from alternator 13.6 . i emptied the transmission filter and then started it then checked the trans filter and it was still empty. so i assumed it was the nylon drive on the flywheel but i took out the hydro pump and the spline is all in tact . does anyone have any ideas . I am assuming the filter should have filled up as soon as i started the machine . I am near brisbane australia and these machines arent common for this area so its hard to get info even from caterpillar . regards , Sam

Replies6
  1. #1Cmark2020-03-22 03:29

    You're correct that CXT is a grey import and not recognised by SIS. If you're also right in using the BYR prefix, and at the moment I can't confirm either way, you should have two charge filters. Is this the situation and if so are they both empty? How did you get onto the BYR prefix?

  2. #2sam123abc2020-03-22 04:25

    Hello, havent checked the second filter yet ( inwards one) as i thought the implement pump also fills it . But if its purely for the hystat pump as well i will check it too. How does the implement pump filter ? i got the byr from the cover of a manual i saw on ebay which covered CXT and BYR so i thought it was the best guess.

  3. #3sam123abc2020-03-22 04:48

    Confirmed : both filters are still empty

  4. #4Cmark2020-03-22 06:27

    Attached hydraulic schematic for BYR prefix. The two charge filters are at coordinates 7G and 8G. If they are both empty then I can't see how the problem can be anything other than a lack of pump drive or lack of hydraulic oil. What filters the implement oil? As far as I can see there isn't anything. Work that one out if you will!?? Do the implements still work?

  5. #5sam123abc2020-03-22 08:19

    OK thanks . one thing i noticed i can turn the pump relatively easy ( using both hands ) . should this happen ? or should i feel some resistance ? Yes implements still work .

  6. #6Cmark2020-03-22 08:26

    So you're saying you pulled the pump stack from the bellhousing and can turn the input shaft by hand? That doesn't sound right. In my experience you should need maybe a two-foot stilson to slowly turn it.