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Rebuilding a La Cimbali Junior

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  • Rebuilding a La Cimbali Junior

    Hi All

    I picked up a La Cimbali Junior grinder recently in a very sorry state.

    Over the past few weeks Ive been pulling it apart, cleaning, repainting, replacing the bearings, etc.

    I thought Id post a few pics. Of course I forgot to take comprehensive before pics, but I think they give you an idea.











    And after -









    The paint was almost completely flaked off of the cast aluminium collar below the hopper and the base plate.

    The burrs were so clagged with old coffee that I couldnt move the burr carrier.

    The doser was similarly caked with old grinds, to the extent that the vanes on the doser had broken and jammed the exit hole.

    I started out thinking I would just give it a clean, and see how things went, but as I progressed more and more bits came off needing cleaning.

    The most interesting part, and one that I havent seen mentioned in other Junior threads around the forums, is that the buildup of coffee in the burr carriage was so great it had spread to the area below the lower burr and damaged the top bearing.

    To get to the bearings I removed the lower burr, three screws. Then I poked a screwdriver in through the exit chute and braced it on one of the three prongs that support the lower burr. This held the motor shaft in place so that I could use a socket to loosen the nut on the end of the shaft - REVERSE thread. After that It only took a couple of gentle whacks to unstick the burr carrier and get to the shaft. Oh, then some whacking to get the shaft and bearing out of the upper motor housing.

    Finally, bearing puller - $20 from Supercheap - and the bearing was off. I took the whole lot to the local bearing place, and they found me a replacement. I bought a pair, top and bottom are the same, and bought bearings with a rubber seal to keep some of that coffee out, $15 for the two. The original bearings dont have a rubber seal.

    The top bearing was absolutely stuffed, it took a lot of effort to turn it by hand once it was off the shaft. I thought the lower bearing was okay, until I compared it to the new bearings, and decided it needed replacing, too. With the new bearings in it is a lot quieter, more of a purr than a roar.

    So, a warning to those looking to buy older Juniors, I think mine is a 96 model, it is worthwhile taking off the hopper and having a close look at how clean the burr area is and turning the shaft by hand to see if the bearings are shot.

    I havent dared to actually use the grinder yet :, its just a bit too clean, maybe Ill wait until the espresso machine turns up and christen them at the same time. At the moment Im using stovetops and a Saeco MC2002.

    I have yet to replace the burr set, or the doser vanes, thats the next task.

    Cheers
    Simon

  • #2
    Re: Rebuilding a La Cimbali Junior

    Good work.

    Comment


    • #3
      Re: Rebuilding a La Cimbali Junior

      Keep posting up the text & piccies Simon, v interesting .


      Cheers..................Sean

      Comment


      • #4
        Re: Rebuilding a La Cimbali Junior

        Thought you all might like a few more pics.

        Some more before -







        Some during -









        And some detailed pics of the top bearing -

        Reverse thread - clockwise - to loosen, braced through the chute with a socket driver.




        Old bearings versus new bearing. The old top bearing is on the top left.
        You can see the red dust shield on the new bearing.


        The new bearing in place-ish. It needed quite a bit of convincing with a socket and a whacker to seat it and replace the circlip.




        With the original burr in place, no thats not coffee.


        And the top burr is even worse. I will be replacing them very soon.


        Cheers
        Simon

        Comment


        • #5
          Re: Rebuilding a La Cimbali Junior

          Excellent work Simon...... [smiley=thumbsup.gif]

          You can tell that these grinders are intended to keep on going for a long, long time. Great series of pics mate 8-),

          Mal.

          Comment


          • #6
            Re: Rebuilding a La Cimbali Junior

            Originally posted by Mal link=1213423685/0#4 date=1213713442
            You can tell that these grinders are intended to keep on going for a long, long time.
            Agreed. Looks nice & heavily built inside.

            Keep up the good work, mate. /thumbs up/

            Comment


            • #7
              Hey everyone,

              I'm attempting this as well an so far it's been going ok. But I struggle to remove the bearings.
              Do I have to take the motor apart for this?
              I tried that and the top and bottom part are moving after I removed the 4 long screws. But the don't go apart.
              How do I remove the top bearing.
              Where is the bottom bearing located and how do I remove it?

              Thanks a lot for your help!

              Edit: I've made a video where I turn the shaft, I would greatly appreciate any opinions about the state of the bearings and if they actually need replacing. I have very little experience with bearings
              Video: https://streamable.com/lv6q6

              Comment


              • #8
                I've actually managed to take the housing apart now with some hammering, hurray!
                Now the next step which I wonder how to manage: How do I remove the shaft and the top bearing?

                Comment


                • #9
                  Well I actually managed to finish this project in the end.
                  I realized with some help from people on reddit that the bearings were worn (they made a subtle grinding noise when they should not make any noise).
                  So I got some replacements with a sealing.
                  But that meant I had to remove the bearings.
                  To do so I had to borrow a tool called a bearing puller. Be warned that it most likely won't work to remove the bearings without damaging them.
                  I managed to remove them with some more gentle hammering and the bearing puller. Be very careful not to hit the shaft, this might bend or damage it.
                  Getting the bearings back on was the next challenge. With this it's important to only apply pressue to the ring of the bearing where you put the bearing onto. So if you put the bearing onto the shaft, apply pressure to the inner ring, not the outer one. If you put the bearing into a housing apply pressure to the outer ring. Otherwise the bearing will probably break since you'll apply force across the bearing balls.
                  To achieve this I bought a piece of pipe with exactly the diameter of the inner ring. Just to be sure I put the old bearing ontop of the new one to lessen the directed impact even more.
                  Then when I had to put the housing back together I would have to apply significant pressure to the bearings mounted on the shaft. To prevent this I heated up the housing parts in a baking oven. This made them extend ever so slightly and I could slip the bearing and shaft right in without any hammering.
                  The electrics were no issue since I took plenty of photos and could put it back together.

                  In the end the machine turned on fine, is now a bit quieter and is grinding my coffee ever since.

                  Here's a lot of the pictures and videos I took of the whole project: https://imgur.com/a/0ZqZrqQ

                  Comment


                  • #10
                    Very nice work. That should last a lifetime now.

                    Comment


                    • #11
                      Indeed...

                      Also got to love the quality of engineering in these older machines - Superb...

                      Mal.

                      Comment


                      • #12
                        Always a good idea to try the local bearing supply for bearings. Often available for a few dollars

                        Comment


                        • #13
                          Originally posted by poorcoffeeman View Post
                          Then when I had to put the housing back together I would have to apply significant pressure to the bearings mounted on the shaft. To prevent this I heated up the housing parts in a baking oven. This made them extend ever so slightly and I could slip the bearing and shaft right in without any hammering.
                          Another way to do this is to put the bearing on an induction cooktop and heat it that way. In industry they use specially made induction bearing heaters.

                          Comment


                          • #14
                            So, thirteen years later after flawless daily domestic use I went for the second cup of the day and all it gives is whirring and stops.
                            big surprise, very sad, since literally no issues since rebuilt.

                            motor start/run capacitor popped it’s socks.
                            new cap on the way
                            new power light
                            new burrs
                            new dose delivery star

                            see ya in another 13!

                            Comment


                            • #15
                              New burrs after 13years ........
                              Ya gunna notice the difference!

                              Comment

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