The GS3 steam lever – precise again instead of spongy
The GS3 steam lever is one of the parts you touch every day. You notice straight away when it is no longer right: it moves too easily, it has play, it does not stay where you put it, or a wisp of steam still comes out of the wand after closing.
This service kit is the overhaul kit for exactly this assembly. La Marzocco lists it under part number B.1.004.K – the same family as the complete steam valve B.1.004.03 and the individual parts B.1.004/3 and B.1.004/4.
When it is due
The lever has play or feels spongy. After closing, it keeps dripping or letting out wisps of steam. The lever travel has lost its clear end point. Or moisture appears at the valve outlet without the valve body itself being damaged.
At a glance
| Type |
Service kit for the steam lever |
| Location |
Steam valve with lever |
| Fits |
La Marzocco GS3 |
| Scope of delivery |
Kit contents as specified by the manufacturer; lever, counter plate and valve are separate items |
| Part number |
B.1.004.K |
| Version |
Overhaul kit, not the complete valve |
| Installation |
Installation by a qualified technician recommended |
| Brand |
La Marzocco |
Important for installation
The lever sits directly on the steam valve and therefore on the steam boiler. Before any work, the machine is switched off, disconnected from the mains, fully depressurised and allowed to cool down. You will deliberately not find step-by-step instructions here: a steam valve is dismantled according to the service documentation for the model, and the order of the small parts decides whether the lever has its clear point again afterwards.
Who it is for
For service workshops that maintain a GS3, and for owners who look after their machine together with a specialist workshop.
What goes with it
The same assembly includes the complete steam valve GS3, the INOX lever and the INOX counter plate. At the transition to the wand sits the brass flange, and the wand itself is the steam wand GS3. Everything for the machine under La Marzocco GS3 spare parts.
Workshop tip from Bern and Zurich
This is our routine, not a manufacturer requirement: after the overhaul, we let the steam run fully open once for thirty seconds, close it and wait a minute. Whatever is still hanging from the tip after that is not there by chance. Then there is a cappuccino made with Nutty Delight – you can taste freshly overhauled steam in the foam. More under Coffee beans.
No returns
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 drop us a quick line and we will clarify the fit together. Your rights in the case of defective goods remain unaffected.
Frequently asked questions
What is included in the kit?
The scope is based on the manufacturer's specification for number B.1.004.K. We do not have a parts list, and we do not list anything here that we cannot back up. Ask us about a specific part before ordering.
Is the lever itself included?
The INOX lever is a separate item with the number B.1.004/3, as is the counter plate B.1.004/4. Both are linked above.
Do I need the whole valve instead?
Only if the valve body itself is damaged – for example with a washed-out valve seat. As long as the body is in good condition, the overhaul kit is the right and considerably cheaper way.
Does the kit also fit other La Marzocco models?
The spare parts list assigns B.1.004.K to the GS3. Other series have their own steam valves and their own kits. If in doubt, send us the model and serial number.
Can I pick up the part from your showroom?
Yes. We have two locations: Bern at Gerberngasse 44 and Zurich at Hagenholzstrasse 50b. Drop us a quick line and we will have it ready.
Questions about the fit? Write to us at [email protected]. We deliver across Switzerland and to Liechtenstein in 2-4 working days.
