J284 backhoe hydraulic control valve leak

Forum Forums Tractor Implements J284 backhoe hydraulic control valve leak

Viewing 11 reply threads
  • Author
    Posts
    • #30852
      edsmtn
      Participant
        • Offline

        The hydraulic control valve on my backhoe is leaking a lot of fluid but everything seems to be tight and can't easily see where it's leaking. It's not the hoses or their connections. Any suggestions?

      • #36689
        ronjin
        Participant
          • Offline

          Which backhoe do you have?

          ronjin

        • #36692
          edsmtn
          Participant
            • Offline

            I have a 2004 Yangcheng hydraulic excavator – model jw03  4d1437 zl20

          • #36698
            ronjin
            Participant
              • Offline

              If your JW03 is the same as mine shown in picture 1, you should be able to disassemble it as in picture 2 to determine the leakage point(s). Picture 3 is an exploded view.

               

              Is it leaking all of the time when the pump is running or only when you perform certain operations?

              http://i289.photobucket.com/albums/ll212/ronj2000/JW03-Backhoe.jpg

              http://i289.photobucket.com/albums/ll212/ronj2000/JW03Backhoe4.jpg

              http://i289.photobucket.com/albums/ll212/ronj2000/BackhoeHydraulics.jpg

              ronjin

            • #36699
              edsmtn
              Participant
                • Offline

                Thanks. Mine looks just like yours. I think it only leaks when I use it. Now that I have it exposed maybe I can pin down just when it is leaking. I think I'll wait till it warms up a little. I just about froze my buns off trying to get at it. The bottom is all wet with fluid but it's not obvious where it's coming from but it's nice and dry where the hoses are connected. I'll fire it up and see if I can see where it's leaking when it warms up a little. 

              • #36704
                edsmtn
                Participant
                  • Offline

                  On the bottom of the valve box there are six weep holes for the six valves. Two of the six are leaking fluid. Any suggestions? Thanks.  

                • #36706
                  ronjin
                  Participant
                    • Offline

                    Is it leaking whenever the pump is running and no controls operated?

                    Or is it only when certain controls are activated?  If so, is it though the whole run of the cylinder or only at fully extended or contracted?

                    ronjin

                  • #36707
                    ronjin
                    Participant
                      • Offline

                      Here is a picture of one of the spools in the control block.  I suspect that you need to replace the o-rings.

                      http://i289.photobucket.com/albums/ll212/ronj2000/BHSpool.jpg

                      ronjin

                    • #36709
                      edsmtn
                      Participant
                        • Offline

                        It leaks only when controls operated.          Ron thank you very much for all your help.  That picture really helps. The o-ring makes a lot of sense.

                      • #36710
                        ronjin
                        Participant
                          • Offline

                          Since it leaks only when controls are exercised, I am pretty certain that it is the o-rings.

                          ronjin

                        • #36714
                          edsmtn
                          Participant
                            • Offline

                            Thanks again Ron. I was wondering where you got the picture of the spool. I had the first picture you sent from the paperwork I got with the tractor but that blowup of the spool was very interesting and wondered the source. Thanks again.   Ed Shea 

                          • #36715
                            ronjin
                            Participant
                              • Offline

                              My picture from several years ago when I had problems with one of my spools.

                              ronjin

                          Viewing 11 reply threads
                          • You must be logged in to reply to this topic.