I have a handful of gaskets on hand, from espressoparts, waiting for a long overdue gasket replacement on our La Pavoni Bar 2L. I've done this before.

The weird thing is, the gaskets aren't all the same. Some of them go on like I expect, others are not nearly stretchy enough.


Good one on the left, bad one on the right. I hope the image shows that the material is much thicker, I suppose that's why they don't stretch.

The image should also show "1017" on the inside of the bad one; on the back is ARINCA or 4RINCA. The good one has no inscriptions.

Anyone know what's up here? I look for "Astoria" parts for this group (made by CMA? I forget), and it takes what espressoparts calls the "old style" portafilter gasket. Has there also been some change in these sleeve gaskets? Is there some kind of piston that could use these non-elastic gaskets? maybe you disassemble the piston to install the gaskets, rather than slip them on over the assembled unit?

Hi,

I believe the Arinca gaskets are for Faema "lever old group" often named "Zodiaco"

Pascal

Interesting. I just got back from the local espresso machine mecca, Visions Espresso Services, and the gentleman I talked to there guessed they might be San Marco - hope I remember that right, but anyway that was just off the top of his head. Luckily he had enough gaskets of the right sort to get me going.

For anyone in or near Seattle with issues like this, it's always a pleasure to drop by Visions, and they always seem to have what I need. It really isn't exactly their core business, retail parts like this, and next time I'll order some more gaskets ahead of time from espressoparts and just check closer that I'm getting the right thing, but in a pinch, Visions comes through again.

Part two: really nothing to do with gaskets, this time. The impetus for this maintenance was poor performance from one of the two groups, and when I had that group out, I saw why:



... the spring is failing, with several cracks.

I gather this is a stainless steel version, introduced after some dissatisfaction with corrosion on the old springs. I had replaced my corroded old springs, but they're still fine, just rusty, so I put an old spring back in service to replace this loser. I'm not sure the other spring is OK - didn't notice any cracks, but it seems to be a little out of alignment, which is probably a sign of this kind of failure.

Springs are under cyclic load, but because of generally good surface finish from manufacturing (no scratches/defects), fatigue (crack propagation) is usually not an issue. Throw in corrosion and you have a different story. The question is, why is water getting onto the spring? Are you servicing the gaskets enough? Or is there an irregularity in the cylinder allowing moisture to sneak past the gaskets?

Edit: actually surface finish on springs usually isn't that great, but still we don't see a lot of surface cracks develop without corrosion.

I'm sure not replacing gaskets often enough, but I doubt that corrosion is the problem. The old spring I replaced this with is thoroughly corroded, but still intact and works great. I understand the reason for stainless springs may have been that the natural corrosion creates a stream of rust particles that get into seals etc. - so it's a problem, but not one that causes the spring to fail until it has gone quite a ways. It would be ironic if the stainless springs, unlike their predecessors, had to be protected from corrosion to keep them alive.

Donn, exactly which group head do you have? Is it an old slender Pavoni style like a P67, or is it a CMA? The CMA has that cylinder sleeve that also needs gaskets too. Looks at Orphan espresso Doug's video on youtube in case you need further help\info.

Yes, it's CMA.