Clean the carburettor on the lawnmower - this is how it works

Clean the carburettor on the lawnmower - this is how it works

Material requirements and tools

Although the specific structure of a carburetor depends on the lawnmower model, largely identical handles are required for cleaning. Competent manufacturers offer repair kits for do-it-yourselfers with all important spare parts such as seals and O-rings. Please provide the following materials and tools:

  • Repair kit for lawnmower carburetors
  • Carburetor cleaner or petroleum ether
  • Compressed air source
  • Rag
  • Tub or large bucket
  • Screwdriver, torque wrench

also read

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If the manufacturer of your lawnmower does not offer a repair kit, you can purchase the required spare parts, such as sealing rings, at the nearest hardware store.

Step-by-step instructions - How to get the carburetor clean

Disconnect the spark plug cable beforehand. As a precaution, keep the wire a safe distance from the spark plug. Then remove the air filter and turn off the fuel tap. On engines without a fuel valve, the fuel line should ideally be clamped off with a clamp. How to proceed:

  • Loosen the fastening screws while the carburetor is still connected to the speed controller
  • In the event of problems, refer to the manual for the positions of the fastening screws
  • Do not remove governor springs until their position has been marked
  • Pour white spirit into a vat
  • Soak the carburetor and all plastic and metal parts in it
  • Alternatively, rub or spray the components with a carburetor cleaning agent

While the lawnmower carburetor is soaking, treat the nozzles and lines with compressed air to remove debris. The air filter and spark plug should also be cleaned on this occasion. Wipe the carburetor and all intact components dry with a clean rag. Please replace damaged or worn parts.

Install and adjust carburetor - this is how it works

Install the clean carburetor and cleaned air filter, re-establish the connection between the spark plug cable and spark plug and open the fuel tap. Please refer to the manufacturer's operating instructions to understand the exact positions of the components. In the last step of the cleaning action, you reset the carburetor. That is how it goes:

  • Start the lawn mower
  • Let it run for a few minutes to allow the engine to warm up
  • Screw in the adjusting screw for regulating the engine speed 1 to 1 1/2 turns
  • The engine speed increases
  • Adjust the adjusting screw for the idle mixture so that the engine runs smoothly and smoothly

Finally, the engine speed is fine-tuned for the perfect idle speed. Ideally, a tachometer for measuring engine speeds is available for this purpose. The optimal values ​​range between 1200 min-1 for an engine with a cast steel cylinder liner up to 1750 min-1 for an engine with an aluminum cylinder.


A carburetor will stay clean longer if you start the lawnmower properly. As soon as the engine has warmed up, the fuel supply should be throttled using the throttle (choke). Otherwise, harmful deposits will form in the carburetor and other components because not all of the gasoline is burned.