I picked up an old Pavoni Europiccola a few months ago and I have had some trouble getting the group to fill completely with water at the beginning of the pull. If I keep the lever raised for about 10 seconds and just push down, the first half of the pull seems to just be pressing air, and I end up with a very small volume (about .6 oz). My solution to this point has been to raise and lower the lever about 2-3 inches multiple (5-6) times. Towards the end of this process I can feel the machine "take up the slack" so to speak, and I get a proper sized pull (slightly more than 1 oz with the double basket and around 14 g of coffee). This works alright, but it occasionally disturbs the grounds and causes side-channeling (I can see it on my naked pf), and forces a very long preinfusion. I'm just wondering if this is a mechanical issue, or if there's a better way around this. I'm filling the reservoir just shy of the top of the sightglass, I let it warm up for a good long time and make sure the safety valve is sputtering away, and if it matters I'm using the kitchenaid proline grinder (I know, not a great grinder, but a friend of mine pulled some shots with a commercial quality grinder and the problem persisted, so I doubt this is the problem). I've also taken the group apart, cleaned with JoeGlo, and checked the seals, which seem to be in good condition.

Thanks in advance for any help you can provide.

After warmup, before loading PF, do a brief flush.

Are you bleeding out false pressure via your steam wand for a few seconds?

Yes, I'm bleeding false pressure, and I typically do a short flush. There's no problem when the pf isn't inserted, so it seems like air is getting trapped in the group. Is the air supposed to diffuse through the coffee when the water enters, or is there an exit hole that might be plugged?

Thanks for the responses.

On my Cremina, the lever would sometimes feel "spongy"on the first shot of the day. After a flush, however, that wouldn't happen; there was good solid resistance starting at the apex. But do make sure you've bled all of the false pressure off.

Do you know how old the Europiccola is?

Some of the early "Millenium models" had nylon pistons which tended to unscrew and reduced the group capacity. The solution is either to screw it back in or replace with one of the later brass pistons.

Cheers

Mike

Re: age, I'm guessing mid to late '80s based on info from previous owner, the double switch (on/off and I/II) and metal sightglass guard. I know for a fact that it has the brass piston, though, from taking apart the group to clean it.

For my EP, I would bleed for about 10ish seconds, flush for a couple of seconds, lift the lever to the top for 5 seconds, slowly pull the lever down until I feel a bit of resistance, hold for a second, lift back to the top - slowly - for another 6 or 7 seconds and then gently but consistenly pull down.

This is a version of the Fellini and whilst you might feel a little bit of sponge you should get close to an ounce. Try that to see if it improves things. It should at least introduce sufficient water without disturbing the puck. Also, tamp lighter and grind finer!

Thanks very much for the replies. I will try ziobeege_72 's protocol and report back.

Best,
Joel

The bleed/flush in quick succession seemed to help a little, but it's still taking multiple fellini moves to develop any resistance on the lever. I'm open to further suggestions, if anyone has any. Thanks again for the help!

I have the same machine and have always had to do the handle "up-down dance" to get rid of the air/steam before a proper pull. I just think that is the way the Pavoni is.

Same here, and it's the same on my La Cara and Pavoni as well, sometimes preinfusing for longer, like 30 seconds, helps.

Mike said,

Some of the early "Millenium models" has nylon pistons which tended to unscrew and reduced the group capacity. The solution is either to screw it back in or replace with one of the later brass pistons.

This mirrors my experience. Eventually the plastic piston works loose and I have to remove it and tighten it. Some plumbers tape applied to the thread seems to hold it better. I was having the same pre-infusion problem as the OP today until I did that little bit of maintenance. Now it works fine again .

Usually the lever in the up position allows plenty of water to enter the group. I generally have no need for the Fellini move.

I'm afraid that if you're getting less than an ounce on a pull with a 10 second preinfusion, especially if a couple of drops fall in the cup, then you either have a problem with your piston mounting, or your seals, or both.

Cheers

Mike

Thanks for the further replies. I have been wondering about the seals, since I already replaced the group-boiler seal due to leakage there, and the lower sight-glass seal went on me last week. Perhaps it's time for an overhaul. OTOH, when I took the group apart they didn't look particularly worn or deformed. Can you tell whether they should be replaced from a visual inspection? And by what mechanism would the seals be causing this problem? Thanks again, all.

Joel

jrm wrote:overhaul. OTOH, when I took the group apart they didn't look particularly worn or deformed. Can you tell whether they should be replaced from a visual inspection? And by what mechanism would the seals be causing this problem? Thanks again, all.

Not necessarily. I have replaced new seals on apparantly fine looking old seals and the difference has been significant. That is because either 1) some tears/imperfections are slight and not easily visible or 2) you can get seepage between the inside of the seal and the piston shaft groove - that you cant see.

Leaky seals means some water/air escapes past the seal itself underpressure, yielding to reduced volume shots. If it is particularly leaky you might see some espresso going back into your boiler. However you should be 'feeling' less resistance in your pull too. Are you getting reasonable resistance as you pull the shot?

Up until very recently I was grinding quite fine, which required a lot of pressure (putting most of my weight behind it, feeling some flex in the lever/boiler -- probably not a good thing). I've backed off a bit now and am starting to feel a bit of slippage in the pull. I haven't really seen grounds in the boiler, but when I cleaned the piston the head had a fair bit of sludge on it. Sounds like replacing the piston seals is the way to go.

Jrm, I wonder if you may just need to adjust your pressurestat?

If it's set too low, the boiler might not be generating enough pressure to get things moving... just a thought.

Thanks for the suggestion, but this Pavoni doesn't have a pressurestat -- pressure is controlled solely by the safety valve. It may be that the spring inside the valve has stretched over time and it's now maintaining a lower pressure, but the temperatures I'm seeing at the grouphead are on the high side, which I think implies high pressure as well (?). Does anyone know if this could be the problem?

It might be, but whether there is a problem or not should be quite apparent if you see how much brew water comes out at the top of the lever pull, under normal pressure, without coffee and basket. If you are getting a good gush at good temperature then you are ok, if it is just weak/dribbly, then that would either be pressure issues or the piston head unscrewing itself from the rod. Sounds like you might be ok here though?