The small nut a fitting depends on
Some parts cost just over a franc and can still hold up a machine. This flat 3/8-inch nut is one of them: it secures a fitting in the water circuit, and if the hex gets rounded off during a service or the thread no longer grips, you can't go a single step further without a replacement.
Part number L183/1.01, height 6 millimetres, AF (spanner size) 21. A simple small part with no moving function.
When it's due
The hex is rounded off and no spanner grips cleanly any more.
The thread is stripped or cracked, and the nut can no longer be tightened down to the stop.
The nut is tarnished or corroded and shouldn't be refitted during an overhaul anyway.
At a glance
| Type |
Hex nut, flat |
| Location |
Fitting in the water and steam circuit |
| Fits |
Various La Marzocco machines; check compatibility using the number |
| Included |
One nut, without seal and without washer |
| Part number |
L183/1.01 |
| Version |
3/8 inch, height 6 mm, AF 21 |
| Installation |
Installation by a qualified technician recommended |
| Brand |
La Marzocco |
Important for installation
The part sits in a pressurised line. Before any work on it, the machine must be switched off, disconnected from the mains, cooled down and depressurised – a boiler is still under pressure hours after being switched off. We deliberately don't give step-by-step instructions here.
When screwing it in, what counts is a clean sealing surface, not force. Overtightening distorts the thread and the sealing seat, and after that it will drip permanently. You're better off leaving this job to a qualified technician or bringing the machine to us.
Who it's for
For workshops that keep an overhaul parts box, and for technically skilled operators who don't want to carry on working with rounded-off nuts during a service.
As our documentation doesn't name a specific model, check the number against your service documentation before ordering.
What goes with it
From our workshop
In Bern and Zurich, we always order small parts like these as well – together with the expensive item you actually need. A service call that fails because of a one-franc nut annoys everyone involved more than the purchase price. That's how we keep our stock, not a manufacturer requirement. Once the machine is leak-tight again, the first shot at our place usually goes through with Very Nutty. Our selection: our coffee beans.
No returns
Original spare parts are excluded from exchange and return. They are sourced to order and cannot be resold after installation or a test fit on the machine. So before ordering, check the model, year of manufacture and serial number of your machine – or drop us a quick line and we'll clarify compatibility together. Your rights in the event of defective goods remain unaffected.
Frequently asked questions
Is a seal included?
No. Only the nut is supplied. Seals and washers are separate items.
Which machine is the nut for?
Our documentation doesn't name a specific model for it, only the number L183/1.01. Send us the model and serial number and we'll check.
How many pieces do I get?
One nut per item. If you need several, simply increase the quantity in the cart.
Can I use a nut from a DIY store?
In the water and steam circuit, material and dimensions matter. We recommend the original part and installation by a qualified technician.
Can I see and collect the part in Bern or Zurich?
Yes. We have two showrooms: Bern at Gerberngasse 44 and Zurich at Hagenholzstrasse 50b. Drop us a quick line beforehand and we'll have the part ready and look at it together on your machine.
Not sure if this is the right number? Write to us at [email protected] with the model, year of manufacture and serial number, and we'll check it for you. Delivery across Switzerland and to Liechtenstein in 2-4 working days.