Hi Craig,

I watched your video there. My guess is that either your piston gasket(s) are old and/or your burner element on the "I" setting isn't getting quite hot enough.

Have you taken the group head off the machine yet to inspect things? There are two bolts that hold it on and a little O-ring that seals it. You should be able to just unscrew the bolts and pop it off. This will allow you to inspect the tube that runs from the boiler up into the group head also and ensure there are no sealing issues with it (where it threads into the group head). If you check my videos on youtube, there is one where I show the machine all taken apart.

I would also check to see how your piston gaskets look and/or if there are any sealing issues. Normally, it's pretty easy to re-install them into the cylinder. Just lubricate with some olive oil and reinsert very slowly with a little, slow twisting action. As far as the lock nut, I normally set that level when I am putting the dispersion screen back on. If you remove the jam nut and the nut on top, then you can press the piston down while holding the dispersion screen in the group head. This should allow you to feel the point at which the piston makes contact with the screen and starts to push it down off the group head. You want to set the nut and jam nut such that the lever stops just prior to pushing the piston into the screen.

On your machine, when you pull up the lever (if everything is working properly and you have the correct pressure), you should feel the water rush into the group head - almost with a gush or a thud. Maybe not a thud, but close. You should feel the water really rush in there, to the point where you can sense this is happening. There should be sort of a rushing or gushing sensation in the machine (which can be felt as well as heard). At the same moment, you should see the water level in the inspection tube on the side of the machine sort of almost jolt down about 1/4 of an inch. Like I say, this is more of an event that you can witness/feel, as opposed to a slow, happy, soft exchange of water from the boiler to the group head. There should be some noticeable lurch almost, as water moves. If you aren't experiencing this, then I think the pressure may be too low in the boiler on the "I" setting.

Also, keep in mind that if the lower sealing gasket on the piston is not producing enough of a seal, then the water will have a return path back to the boiler (both during filling, as well as when you press the lever down). Higher heat may help produce a better seal, in this regard, so this can also explain why the higher heat setting may be working better.

In your video, the last shot you pulled look more on the order of what you should be seeing. Based on how the shot came out, it looked like your grind/tamp might have been off slightly. However, from what I could see with the shot, it looks like you were in the ballpark and very close as far as getting a really nice shot. I would guess just 1 click away on the grind setting and/or maybe +/- 5 lbs on the tamp.

Have you tried turning on the machine to the "I" setting with the boiler cap removed? You might want to give that a try in order to see if the water is actually getting hot enough from just the "I" element. However, if you are hearing steam when the machine is on this setting, I would presume it's getting hot enough. BTW, have you inspected the wiring yet? I think I mentioned checking the connections in an earlier post. It's not uncommon for the connections to dry out a bit and lose some of their electrical connection. Make sure the machine is unplugged of course. When I bought my La Pavoni and went through it, I found that two of the electrical connections were not making proper contact (where the wire went into the crimped part of the spade connectors).

Ray

gegtik wrote:The locknut at the top controls how far *down* the piston travels, so I am guessing when you say the piston may have unscrewed, you mean the rod that fits into the piston head? In other words, where #42 screws into #44 in this diagram http://www.partsguru.com/user/LaPavoni%...gram-2.JPG ?

Thanks

I think he's referring to where the brass piston body threads onto the rod that goes up to the lever. If the piston were to unscrew, it would not retract up far enough in the cylinder and could then tend to block the entry holes that allow water to flow into the group head. I think that's a long shot, but it's certainly worth checking! Definitely good advice as far as possible things that could be causing problems.

The time is now: remove the group head and pull out the piston!! We are all pulling for ya

Ray

So, I opened my europiccola up again to inspect the piston, and here's what I've found:



the top two pictures show the water inlet from inside and outside the grouphead.
the bottom pictures show the grouphead with the piston inserted and fully drawn upward.
in the first image, you see how far up the piston travels, as viewed from inside the grouphead
in the second image, you see through the water inlet holes as viewed from outside the grouphead (where the siphon screws in)... detail:



The third picture is the same, only I am shining a flashlight through the grouphead... detail:



In the last two pictures, the top of the grouphead is to the right, and the dispersion screen would normally be on the left.


I notice a couple of things here:
1. the inlet holes are never fully exposed to the grouphead, even when the piston is fully lifted. they are somewhere between the bottom piston gasket and the bottom of the piston. This means the water has to push past the side of the piston before entering the brew chamber itself.
2. one of the holes is higher than the other
3. one of the holes is bigger than the other
4. it looks like the gasket is partially blocking both of the holes.

Are any of these things normal?
If not.. is there anything I should do about it? Should I try to drill the holes bigger??

Thanks for any advice that you can offer

- Craig

Pull out the piston and make sure it's tightened on the piston rod. 42 and 44 on your diagram.

mikekarr wrote:Pull out the piston and make sure it's tightened on the piston rod. 42 and 44 on your diagram.

I have -- it's so tight I can't even unscrew the rod from the piston body.
I tried putting a metal bar through the hole in the rod and grasping the piston body with a pair of vice grips and a towel.. I was unable to budge it. I even tried heating up the piston in case it would help, but nothing did.

I hope it's tight enough because I don't tihnk I can do anything about it
I think the only way to bring it up higher is to grind down the top of the brass piston a little?

Everything looks normal as near as I can see. Do not start grinding stuff randomly. Locate the issue (if there is one) and fix that.

Do you have a picture of the piston removed, showing the gaskets?

Ray

Here you go Ray..

Given the problem you report, I'd switch the spacer gaskets to the other side of the V gaskets.

Interesting.. my piston has slightly different gaskets on it as I recall. I don't think mine had those spacer looking gaskets.

Ray

RayJohns wrote:...What I usually do is turn the machine on and let it heat up for about 5 minutes on the "II" setting, then when steam starts coming out of the safety valve, I flip it down to "I" and leave it. I'm able to get very good espressos from it...

The biggest knock on the Pavoni is that the group overheats and the overheated group gives the coffee a burnt taste. The group, on the Pavoni "pre", will overheat on both the I and the II setting. The machine needs to be turned off, as much as possible, to prevent the group from getting too hot.