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Restoration of a La Pavoni P67

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  • #16
    Another tool arrives on the doorstep! It's a nice face spanner tool with swappable metric sized pinions. I think it is used for vehicles, but I got it for the piston disassembly and will also be useful on my Boema. It is much bigger than I thought, that square hole is for a 1/2" drive if you need more leverage and the base tool is already a foot long!


    I heated up the piston and struck it on the face with a mallet before I placed the upper group in the vise by the bearing bolts. The hole size is 5mm on the piston face, and with a nice firm tug the tool worked perfectly and the piston began unscrewing. The mountains of grease likely keep the threads of the rod and piston in pristine condition, and when I started unscrewing the piston a strong smell reminding me of an oily smell seen on museum ships entered my sinuses. I placed a few zip ties but it was not needed as the thread is longer than the fully relaxed spring.



    With the piston and spring off I could take off the bearing bolts with a 17mm deep socket wrench. This allows the lever fork to be maneuvered up and out of the upper group casting with the two-piece rod. The rod pin has a knurled end, so I did a light tap on the opposite side to release the fork from the rod assembly.

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    • #17



      There is another pin to take out between the lower rod and the upper rod with two bushings along with the internal ball bearings in the upper group casting, but I will clean off the mountains of grease before proceeding. Modern Astoria CMA seals work with this piston, so I intend to get the silicone ones from Cafelat when possible. The spring can also be replaced by the modern 140mm spring on Pavonis and CMA machines if needed.


      At this point it's just the boiler and machine frame that need some more work before everything is apart, and then I can begin the cleaning process. The parts order is mostly assembled, just need to confirm one or two things before proceeding forward.

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      • #18
        I stripped the rest of the Pavoni frame today. It's really nicely thought out in where the bolts are located. Note the frame is comprised of an upper and lower frame, the latter holding the gas assembling, drain tray, power switch, and water inlet, while the upper frame holds the boiler and panels.

        It was all M8 bolts, and while rusted they came out without issue. I could then take off all the remaining bits except for one foot (again?!). At least my Boema's two remaining feet are already off 😂. Historically getting my frame powdercoated could affect the panels going back on due to the added thickness from the powdercoat (this was worst for me on the Mercurio in terms of impact). However for the Pavoni I am 95% confident this would not affect me since the upper panels have a small gap in the first place to fit onto the frame, so this leeway is where the powdercoating layer will go (if that makes sense). The colours will be grey for the upper frame and black for the lower frame.





        A last thought is the piston. I cleaned it up and got some measurements for it as a friend wanted to confirm some measurements on a prior-gen grouphead he has for seal purposes. It's unlikely it is compatible but it does not hurt to check.

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        • #19
          The boiler flange is not playing nice with me, so I put it in time out and a soak in ATF to work on getting the heating elements out. In the meanwhile I tackled the nasty task of getting all the grease off the group pieces. This is a multistep process that can be summarized as the following:
          1. Wipe off as much grease as I can
          2. Use a degreaser like GUNK Engine Cleaner
          3. Rinse and wash parts in ultrasonic cleaner with Joe Glo or related coffee cleaner
          4. Repeat as necessary

          I first needed to take off the second, smaller pin connecting the two rod pieces and the bearings. After a quick heating the grease acted as a lubricant and I could very lightly tap them all out without hassle. The pin is the same diameter as the one going into the lever fork but shorter in length. The bearings are tiny compared to the Faema or Boema ones, and one is made in Germany and the other in Italy. If I really needed to they could be reused. After I proceed to hand wipe the grease. It was not fun and I could not take many pictures due to how much got on my hands.




          Step 2: Degreaser. Note I was cleaning some Lambro parts in tandem so you may see some Faema parts in the mix.


          Step 3: Ultrasonic Cleaner. The sticker absolutely needed to be preserved so I never let it touch the water.

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          • #20


            I was very pleased with the outcome, and everything is nice and clean. Holger was correct with the little markings noting where the knurled part of the pin lies on both the lever fork and lever rod.




            Once small concern is a hole I discovered in the upper group casting that holds the fork and bearings. I believe I am ok because the cylinder is not load bearing and simply guides the lever rod.

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            • #21


              The lever fork has a damaged thread as well that I will need to repair/re-tap. It is the same thread as modern Astoria levers (like my Bosco, which I tested this theory with).

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              • #22
                The frame is fully stripped and I can send it to the powdercoaters, but in the process I accidentally popped out the rubber foot from its bolt so I will need to get it back on. I will wait for my Lambro to be fully stripped then I can place one big order for the powdercoating.


                I have all of the gasket sizes sourced for the Pavoni except for one: the packing gland of the steam/hot water valves. I measured it to be 20x9x15 mm, and even if I used three 20x9x5 mm gaskets these would not be common. I could instead pack it with hemp, does anyone here prefer a specific product for this purpose?

                One little amusing thing I saw was the Pavoni inlet rod uses the same gaskets as my Gaggia LL/Tell valves, a 15x6x3.5mm gasket and two 2015 o-rings. The Pavoni rod is above and a Gaggia rod is below.


                The boiler and lid have been soaking in my bucket of citric acid. I knocked out the heating elements with a pin and mallet. Also note I said one was 300W and 1000W. In fact they are both 650W.

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                • #23
                  I took the lid out after about a day to take off the fittings. This is one of the rare times I prefer a close fitting crescent/adjustable wrench over my regular 21mm wrench for the 3/8" BSP fittings because it has more leverage for me to use, and it is not offset like my socket wrenches from the head of the fittings (which can be an issue if exerting large forces). I get the wrench to be as tight as possible and wack it on the end with a strong strike. With the lid clamped into my vise I got four of the five fittings off. The last elbow fitting will be an odd one to take out as there is no flat surface to grasp it with a wrench. That one may need some thought.




                  You can already see I will have a fun time with the 5 snapped bolts. The boiler face looks pretty and I hope to clean it up well after.

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                  • #24
                    I re-tapped the thread in the lever fork and lever for the Pavoni. As stated earlier it is identical to modern Astoria/CMA groups: M16 x 1.5 thread. Before I could not screw the lever in due to the damaged thread but that is now fixed. While looking at the photos I would like the opinion of others one whether the lever should be rechromed due to the many speckles of rust where the plating has come off. I am unsure whether to through with that or not as I do not want the lever to look 'off' with the rest of the group. The lever fork should be cleaned up after a polish at the neck where the lever screws in, and the rest of the fork is mostly obscured by the decorative cap.



                    I've been trying to get the boiler fittings off still. I succeeded with the t-fitting on the group flange but the other three remaining fittings will not budge. My minimum goal is to at least have the hot water connection fitting to come off. I hate leaving the original hemp cord sealant but I really do not want to bend or damage the soldered fitting joints in the boiler that the fittings screw into. The boiler lid I gave to my metal guy to remove the sheared off element bolts, I want it done correctly and even if I wanted to I do not have a big enough drill press to drill out the bolts and retap myself (if it came to that).



                    I have been looking at the panel frame for the exterior. I am not seeing much damage or scratches. I saw only two very small dents that can be observed only when looking closely in the pic, and the majority of scratches are on top, presumably from something that rested on the machine at some point. I think I will simply wash the frame and keep it as is.

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                    • #25
                      My inexpert opinion is that the lever needs to be rechromed. I have a feeling the pitted lever will look more odd than a newly chromed lever.
                      However, assuming you can significantly clean up the lever, see how it looks in a cleaned state before committing it to the chrome plater.

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                      • #26
                        Great to see another of these out there. I've got a 2 group from 1970. It looks like they changed the taps and sight glass in between.

                        I'd try buffing the lever with aluminium foil as it cleaned up the chrome well on mine.

                        At the moment I'm trying to work out the shower screens and group seals, the new clip ons I've tried dont fit well. Would be good to know which fit yours.

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                        • #27
                          Aluminium foil removes rust using a low temperature version of the thermite reaction:

                          2 Al + Fe2O3 -> Al2O3 + 2 Fe

                          but therein lies the problem: the aluminium oxide is a very effective abrasive and will leave tiny scratches on the surface.

                          This may or may not be a problem in a given application but it's worth being aware that it is there.

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                          • #28
                            Inspirational stuff. Such a big job.

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                            • #29
                              The group seals should be the same as modern Astoria/CMA lever group seals. The shower screen is unique to Pavoni. I got a spare from Brooks Espresso machines but I have the original one as well.

                              I am proceeding forward rechroming the lever after cleaning up the fork, they really do not fit well together as is.

                              I considered leaving the scratches on top but in the current spot directly below the light they are irking to me. I will have to look at the panels in other light to see how egregious the scratches show. I decided to go forward with redoing the red panels to make sure I have all the asbestos removed. I have a very close if not exact color sourced: RAL 3004.

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                              • #30
                                With some aid I managed to save all of the boiler lid heating element threads. That aid was oxy-acetylene, done by my metal guy. He noted there was some sort of thread sealant used from an odd coloured liquid bubbling out during heat up, which may explain the resistance of the bolts coming out. The threads will be cleaned up with a tap. I can finally clean up the lid of remaining grease and crud.



                                I decided to renege on my intention to rechrome the lever, rather I will try to keep everything as original as possible. In fact the only things getting new chrome are the portafilter, the steam wand, and hot water wand since those actually have a lot of chrome flaked or rubbed off. I also decided to redo the red panels with a new powdercoat to ensure all rust and remaining asbestos remnants are taken off. I asked Paul Pratt what he used and with some confirmation it is RAL 3004 to be the closest equivalent to the panel colour.



                                The stainless steel panels will be very lightly cleaned up, with the top rails being sanded in an attempt to get the big scratches off.

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