Just before the guarantee on my machine ran out, it began to drip from both the steam pipe and the group. As well as being messy this was very annoying as the amount of water available for coffee was very much reduced. I took it back to the shop. When I got it back, a week later it was worse, water now gushed from the group and the steam pipe still dripped. This meant another long trip across London, and another week without real coffee. The shop said they could find nothing wrong with it when I collected it the second time, but plainly they had replaced the seals again. The machine was still not entirely satisfactory but I really couldn’t be bothered to take it back. I put up with drips for another 6 months before deciding to attempt the repair myself. I reasoned that if I couldn’t repair it I would buy a Silvia. Fortunately the repair is quick, easy and the machine is now almost as good as new.
I live in the UK and got my parts online from
http://www.fairfaxcookshop.co.uk
A full set of seals, plus lubrication cost about £13
I used this site for instructions
http://www.pavoniexpress.com/
I don’t intend to duplicate this information just to add comments and pictures.
Before starting to do any repair on a Pavoni, UNPLUG IT FROM THE SUPPLY and empty the machine of water.
Collect the tools you will need.
1. Small screwdriver
2. Sharp nose pliers
3. 10mm and 14 mm spanners
4. A bowl plate or something to put small parts in.
Remove the lever - I find a small screwdriver is the easiest way to get cir clips off, watch out they tend to fly off and get lost.
Note: - the holes drilled in the lever are not symmetrically drilled, top to bottom. Make sure when you come to put it back together you get it the correct way up.
Remove the group. I don't know why some people are reluctant to do this, it's very easy, just two 10mm bolts.
At about this point put the new seals in a bowl of boiling water to soften them. (Larger than in the picture so that it stays hot for at least 10 minutes) This makes them easier to fit.
Hold the group and push the piston rod down so that it pushes the shower screen and gasket out to the bottom of the group. This can be a bit tough if it’s been a long time since it’s been apart. A mallet might be necessary, but don't go mad. Once the piston is out, you can start cleaning the piston face, the shower screen and the inside of the group. I think the first time I did this that one of the piston rod gaskets had disintegrated because there was a huge amount of oily debris behind the piston.
Once everything is clean, remove and exchange the piston rod seals. This is straight forwards, if a little fiddly. Next remove the piston seals, you can be brutal at this stage but don't damage the piston. The new seals should be soft by now. They are easily damaged, so having damaged my first set. I now try to fit them without using any tools. The seals have a triangular cross section, once fitted their surfaces should slope in towards each other, see photo. It’s just a case of stretching them around the piston until they slot in, but make sure you get them the right way up.
Next smear a small amount of lubrication on the piston rod. I really don’t think any lubrication is needed on the inside of the group. It’s all going to come out in the coffee eventually anyway and does nothing to help the reassembly process.
Re fitting the piston into the group is the next point at which it’s very easy to damage the seals. I have to admit that I used to advocate just the used of fingers for this stage. However the last time I did this job I could not get the piston back in. So use a screwdriver or whatever, just don't panic, and be gentle, it will eventually go back in.
To re fit the screen, hold it in place, then using a blunt instrument, such as half a peg push the seal into the gap. Its not really necessary to spend long getting a tight fit here because the porta filter will really push this seal in tightly.
The rest of the reassembly is straight forwards; just remember to get the lever the correct way up. Before putting your spanners away it’s worth adjusting the nut on the piston rod. Push the screen filter fully home, then pull the lever down. At the bottom of it's travel the piston should be very close to the screen but not touching it. Once adjusted tighten the locking nut.
The end result should be a machine that no longer drips.