The 0,8 mm bore for groups that should come up to pressure faster
The gicleur is the small stainless steel screw with the precise bore that sits in the water path to the brew group. It limits how much water can flow in per second. At 0,8 mm, this is the wider of the two common versions: shorter pre-infusion, faster pressure build-up, more pace at the start of the shot.
If it clogs, you notice it first in the timing. The shot drags on, the needle climbs more slowly, and the machine feels sluggish even though nothing is wrong with the pump or boiler.
Descale first, then replace
A gicleur is almost always just scaled up. 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. A new gicleur is only worth it if the bore is eroded or the thread is damaged.
When it's due
You need a replacement if the flow stays too high even after descaling, if the hex is rounded off, if the thread no longer grips cleanly, or if someone has widened the bore with a wire.
At a glance
| Type |
Gicleur (flow jet), original spare part |
| Bore |
0,8 mm |
| Installation location |
Water path to the brew group |
| Fits |
La Marzocco machines with part number A.5.100 – send us the serial number and we'll check the fit |
| Scope of delivery |
one gicleur, without O-ring |
| Part number |
A.5.100 |
| 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 workshops and operators who want to restore the original flow behaviour of their group after an overhaul.
What goes with it
The narrower bore is the Gicleur Ø 0,6 mm M4. Related items 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
Switching from 0,8 to 0,6 mm changes the machine's profile, not just a spare part. In Bern and Zurich we first note the shot time and output volume, then swap and measure again – otherwise you end up discussing a feeling instead of numbers afterwards. That's our routine, not a manufacturer specification. We measure 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.
How does 0,8 differ from 0,6 mm?
0,8 mm lets more water through: shorter pre-infusion, faster pressure build-up. 0,6 mm makes the start gentler.
Is an O-ring included?
No. Only the gicleur is supplied.
Can I simply switch to a different size?
Technically yes, but it changes your extraction profile. Note the time and volume beforehand so you can compare afterwards.
Can I see the part in the showroom?
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.
Questions? Write to [email protected]. Delivery across Switzerland and to Liechtenstein in 2-4 working days.
