The KB90 gasket sits accurate to a tenth of a millimetre
The KB90 uses a portafilter that slides straight in rather than being twisted in. To keep it sealed, the group gasket has to be set to a specific dimension – too deep and the portafilter is hard to insert, too high and water runs past the edge. This tool sets that dimension.
Without a gauge, setting it becomes trial and error: fit it, pull a shot, it drips, take it out again. With the gauge it is done in one pass – and repeatable, even if someone else is working on the machine next year.
When you need it
The tool is not a wear part but basic equipment for any workshop that services KB90 machines. Order it if you replace the group gasket yourself, if water escapes at the edge of the portafilter after a gasket change, or if the portafilter has become stiff after a service.
At a glance
| Type |
Calibration tool for the group gasket |
| Installation location |
Workshop tool, does not remain in the machine |
| Fits |
La Marzocco KB90 |
| Scope of delivery |
One tool. Gaskets and anti-shock plates are separate items. |
| Part number |
UT023 |
| Design |
Our documentation gives no information on material or dimensions |
| Brand |
La Marzocco |
Who it is for
For service companies and for hospitality businesses with their own technicians that have a KB90 on site. If you replace the gasket once a year, the gauge saves you half an hour of trial and error at every service – and the complaint that would otherwise come two weeks later.
What goes with it
The matching gasket is the group gasket including two anti-shock plates. The same assembly includes the complete piston for the group head, the service kit for the straight-in piston and the portafilter holder kit 2.0. Everything else is in the KB90 spare parts section and under Original spare parts.
From our workshop in Bern and Zurich
After every gasket change on the KB90, we slide the empty portafilter in and out three times before the first shot – a fresh gasket settles, and what was still tight on the first insertion is just right by the third. That is our routine, not a manufacturer specification. The shot afterwards is a Nutty Delight for us; if you like it darker, take the Cozy Chocolate, if you want punch, the Very Nutty. You will find all of them under Coffee beans.
Returns excluded
Original spare parts are excluded from exchange and return. They are procured specifically for each order and cannot be resold after installation or test fitting on the machine. So before ordering, check the model, year of manufacture and serial number of your machine – or send us a quick message and we will clarify the fit together. Your rights in the event of defective goods remain unaffected.
Frequently asked questions
What exactly do I need the tool for?
Our documentation lists UT023 as a tool for calibrating the gasket on the KB90. It sets the dimension to which the group gasket is adjusted.
Is a gasket included?
No. The tool is what is supplied. We list the gasket and anti-shock plates as separate items.
Does it also fit other La Marzocco machines?
Our documentation lists only the KB90. Tell us which machine you have and we will check before you order.
What are its dimensions?
We have no information on this, nor on the material. The only reliable reference is the part number UT023.
Can I pick up the part at your shop?
Yes. We are in Bern at Gerberngasse 44 and in Zurich at Hagenholzstrasse 50b. Send us a quick message saying which part you need and we will have it ready.
Questions about fit? Write to us at [email protected]. We deliver across Switzerland and to Liechtenstein in 2-4 working days.
