The 0,6 mm bore that tells the water how fast it may flow
A gicleur is nothing more than a screw with a very precise hole. Fitted into the water path, it throttles the flow and so determines how gently the group starts. 0,6 mm is the narrow version: slower pressure build-up, longer pre-infusion, less disturbance in the coffee grounds.
Because the bore is so small, a thin layer of scale is enough to change how the machine behaves. The shot gets longer, the pressure arrives later, and the recipe that worked for years suddenly no longer fits.
Descale first, then replace
A gicleur is almost always just blocked, not broken. Remove it, soak it overnight in descaling solution, rinse it clean and hold it up to the light – if you can see light through the bore, it's good again. You'll find suitable products in our cleaning range for machine and grinder, such as the descaler or, as a preventive measure, the descaling pad for the water tank. Buying a new one is only worth it if the bore is eroded, the hex is rounded off or the thread is damaged.
When it's due
You need a replacement if the shot still runs too fast even after descaling – a sign of an eroded bore –, if the hex is rounded off, if the thread has been damaged, or if someone poked a wire through the bore during the last repair.
At a glance
| Type |
Gicleur (flow jet), original spare part |
| Bore |
0,6 mm |
| Installation location |
Water path to the brew group |
| Fits |
La Marzocco machines with part number A.5.108 – send us the serial number and we'll check the fit |
| Scope of delivery |
one gicleur, without O-ring |
| Part number |
A.5.108 |
| Version |
M4, wrench size 4, stainless steel |
| Installation |
Installation by a specialist recommended |
| Brand |
La Marzocco |
Important for installation
The gicleur sits in the pressurised water path. Depressurise the machine and disconnect it from the mains first, then run a test shot under observation. We deliberately do not provide step-by-step instructions here.
Who it's for
For service technicians and ambitious operators who want to restore their flow profile after scale or a careless repair has altered the bore.
What goes with it
The wider bore is the Gicleur Ø 0,8 mm M4. Related parts are the Gigleur 0.6 mm for GS3 and Strada AV and the flange gasket for the GS3 brew group. Everything else under La Marzocco accessories and spare parts and Original spare parts.
Tip from our workshop
We never poke a wire through a gicleur bore. Even stainless steel gets a burr, and after that the water never flows the same way again. At our places in Bern and Zurich there is only descaler and patience – followed by a shot on the scale to see whether the time is right again. That's our routine, not a manufacturer specification. We dial in with Nutty Delight, Cozy Chocolate for chocolatey notes or Very Nutty for body. All roasts under Coffee beans.
No returns
Original spare parts are excluded from exchange and return. They are sourced specifically for each order and cannot be resold after installation or a trial fitting on the machine. So before ordering, check the model, year of manufacture and serial number of your machine – or drop us a line and we'll clarify the fit together. Your rights in the case of defective goods remain unaffected.
Frequently asked questions
Do I actually need to replace the gicleur?
Usually not. A night in descaler usually clears it again. A replacement is needed if the bore is eroded or the thread is damaged.
What does a different bore change?
A narrower bore lengthens the pre-infusion and makes the start gentler; a wider one lets the machine come up to pressure faster.
Is an O-ring included?
No. Only the gicleur is supplied.
How do I know whether A.5.108 is the right number?
The safest way is via your machine's service documentation. Send us the serial number and we'll check it before you order.
Can I see the part in the showroom?
Yes, you can see it in person in Bern (Gerberngasse 44) and Zurich (Hagenholzstrasse 50b).
Questions? Write to [email protected]. Delivery across Switzerland and to Liechtenstein in 2-4 working days.
