Nine millimetres that keep the pressure in the portafilter
The group gasket is the part of an espresso machine that wears out fastest and has the biggest impact. It sits between the brew group and the portafilter and keeps the pressure where it belongs with every shot. Once it hardens, some of the pressure escapes sideways – and you taste it before you see it.
This gasket is the older version, 9 mm thick, part number H.3.002. It is not the same as the 8 mm version fitted to the GS3 and the commercial machines. If you fit the wrong thickness, you notice it immediately at the portafilter handle: it either ends up much too far to the right or will barely lock in.
When it's due
- Water runs out at the side of the portafilter during extraction.
- You have to turn the handle further and further before it seals.
- The gasket is hard, shiny, cracked or burnt in.
- The portafilter can only be released with a lot of force.
- After extraction the group keeps dripping, even though the shower screen is clean.
At a glance
| Type |
Group gasket, 9 mm, older version |
| Installation position |
Between brew group and portafilter |
| Fits |
La Marzocco groups with a 9 mm gasket seat. The documentation does not name a specific model – the number H.3.002 is what counts. |
| Scope of delivery |
One gasket. The shower and shower screen are not included. |
| Part number |
H.3.002 |
| Version |
Original spare part, 9 mm |
| Brand |
La Marzocco |
Not to be confused
La Marzocco has several group gaskets, and they look confusingly alike. This one is the older version with 9 mm. The 8 mm gasket for the GS3 and commercial machines is a different item, as are the gaskets for the Linea Mini, Linea Mini R and Micra, for the LEVA and for the KB90. Measure your old gasket or send us the serial number, and we'll tell you which one fits.
Who it's for
For owners of older La Marzocco groups who change the gasket themselves, and for workshops that need a stock of both thicknesses for servicing.
What goes with it
The 8 mm version is the group gasket for GS3 and LM commercial machines. For locking there is the bayonet ring for the brew group. Suitable cleaners can be found at Puly Caff Plus and in the machine and grinder cleaning section.
From our workshop in Bern and Zurich: We change the group gasket based on the number of shots, not by feel. In a bar, for us that means twice a year; at home, about once. If you wait until it sprays out at the side, you've already been working with too little pressure for weeks – and looking for the cause in the grinder. That's our routine, not a manufacturer specification. After the change we dial in again, ideally with the Nutty Delight or the Cozy Chocolate, and for strong milk drinks with the Very Nutty. Everything is in our coffee beans.
Returns excluded
Spare parts are excluded from exchange and return. They are sourced specifically for each order and cannot be resold once they have been installed or test-fitted on a machine. So before ordering, check the model, year of manufacture and serial number of your machine – or drop us a line and we'll work out the fit together. Your rights in the case of defective goods remain unaffected.
Frequently asked questions
9 mm or 8 mm – which one do I need?
Measure the old gasket or look up the number in your service documentation. This one is H.3.002 with 9 mm, the other version is 8 mm. If in doubt, send us the serial number and we'll check it in advance.
What does “older version” mean?
That's how La Marzocco lists this gasket in its documentation. It is intended for older groups that still have the 9 mm seat. That's all it says there – and we don't add anything we can't back up.
How often should I change it?
That depends on throughput. In a bar usually every six months, at home about once a year. If it gets hard or sprays out at the side, it's time anyway.
Do I need to change the shower screen as well?
Not necessarily. If the group is open anyway, it's worth a look: a clogged shower screen costs more extraction quality than a tired gasket.
Can I see the part at your shop?
Our showrooms in Bern (Gerberngasse 44) and Zurich (Hagenholzstrasse 50b) show a wide selection, but not our entire range – the display changes. Drop us a quick line at [email protected] before your visit, and we will check whether the product you have in mind is currently there. Bring your old gasket along and we'll measure it.
Questions about the fit? Write to us at [email protected]. We deliver across Switzerland and to Liechtenstein in 2-4 working days.
