How to replace the rubber gasket on an Italian coffee maker

Moka coffee machines are undoubtedly one of the most robust and durable coffee machines. If you have a good quality Italian coffee maker and use it correctly, it will probably last for decades. These coffee makers have a very simple design. Still, it works perfectly if you keep the coffee makers clean and well-maintained.

The rubber gasket of an Italian coffee machine is one of the three intermediate elements (between the filter plate and the funnel tank) which separate the upper body from the lower body. The gasket is located inside the Moka. Its function is to seal the inside of the coffee machine so that water does not escape during the coffee brewing process.

As the water temperature and pressure rise during the brewing process, water will escape through the junction between the bottom and the top of the Moka pot without the rubber gasket (or with a damaged one).

Due to these high temperatures, the rubber gasket suffers and deteriorates. However, silicone gaskets are now widely used, a material less sensitive to these changes, alleviating this deterioration. Fortunately, just as they deteriorate, they are also easy to replace, and their price is not excessively high.

Parts of the Italian coffee maker - How to replace the rubber gasket on an Italian coffee maker

Buying a rubber gasket for an Italian coffee maker

When buying a rubber gasket for your Italian coffee machine, the main thing is to ensure that the gasket you buy has the same dimensions as the one you will replace.

Above all, you need to ensure the gasket’s outer diameter, as most have a width of about 0.8 mm (difference between outer and inner diameter), which covers the filter plate more than sufficiently.

If your gasket has been ruined, perhaps you have lost it; you can still measure the outside diameter at the base of the top of your Italian coffee machine. As shown in the picture below, you must measure where the threaded part of the kettle ends (left) or the gasket’s outer diameter (right).

Measuring the outer diameter of the rubber gasket
Measuring the outer diameter of the rubber gasket

Related: Spare parts for coffee machines

You must measure the outer diameter of the gasket or kettle’s base rather than going by what sellers advertise in their shops. I have seen many times contradictory data on supposedly the same gaskets. This is because not all manufacturers use the same dimensions to build their kettles.

Therefore, when buying a rubber gasket, don’t look for the number of cups your Moka pot brews. Still, the actual dimensions of the rubber gasket it incorporates. This will save you from returning the product and fighting with the seller.

NOTE: Some brands, such as Bialetti, do not specify the measurements on their rubber seals but the size of the coffee machine. For example, 2 cups, 3 cups, etc.

How much does a rubber gasket for an Italian coffee maker cost?

As with all products, it depends on the brand and the origin of the gasket, but prices range between £4 and £8. Packs of 3 or more gaskets are usually available; some offers include the filter.

How to change the rubber of an Italian coffee machine – Step by step

  • First of all, the coffee machine must be disassembled. Separate the boiler, the upper body, the filter plate, the rubber seal and the water funnel.
  • Make sure to clean the edges that come into contact with the rubber or silicone gasket. You can also use this step to clean or replace the coffee machine’s filter plate. It is not essential, but you must disassemble the parts.
  • Place the new gasket on the filter and fit the two main parts of the Moka (upper and lower).
  • Final check: fill the coffee maker with water and imitate the coffee-making process to ensure there is no water leakage.

How often should I change the rubber gasket on my coffee maker?

On the one hand, whenever you see some water or steam escaping between the upper and lower body of the coffee machine, you should change the rubber gasket as this is one of the unmistakable signs that something is wrong. We assume that you have closed the coffee maker properly.

You can also change it once a year as routine maintenance, but this frequency will depend on how often you prepare coffee with your Italian coffee maker. If you brew only a few coffees a day, you can wait two years or until it is damaged.

You should clean the entire Moka pot thoroughly, including the rubber gasket, weekly. Use soap and water and clean all components thoroughly so that the rubber seal will last much longer in good condition.

Related: Bialetti Troubleshooting.