Deterioration and Oxidation of Petrol

Depending on the region where you operate your equipment, fuel formulations may deteriorate and oxidize rapidly. Fuel deterioration and oxidation can occur in as little as 30 days and may cause damage to the carburettor and/or fuel system. Please check with your servicing dealer for local storage recommendations.

Petrol will deteriorate and oxidize in storage. Old petrol will cause hard starting, and it leaves gum deposits that clog the fuel system. If the petrol in your lawnmower deteriorates during storage, you may need to have the carburettor and other fuel system components serviced or replaced.

The length of time that petrol can be left in your fuel tank and carburettor without causing functional problems will vary with such factors such as the additives in the particular brand of petrol, your storage temperatures and whether the fuel tank is partially or completely filled. The air in a partially filled fuel tank promotes fuel deterioration. Very warm storage temperatures accelerate fuel deterioration. Problems as a result of fuel deterioration may occur within a few months, or even less if the petrol was not fresh when you filled the fuel tank.

To prevent fuel related problems:

  1. Start and use your machines regularly. This will ensure a flow of fresh petrol through the fuel system. Keep the tank completely filled, as air in the tank will promote fuel deterioration during storage.
  2. If you suspect that your petrol has already oxidized, it will be best to completely drain the old petrol from the fuel tank. Fill the fuel tank completely with fresh petrol and then run the machine for a few minutes to ensure the fresh petrol replaces the old petrol in the carburettor.
  3. If you intend storing the machine for a longer period of time, It is suggested that you add a petrol stabilizer to the fuel. After adding the stabilizer product to the petrol, it is important to run the engine for at least 10 minutes to ensure that the treated petrol has replaced the untreated petrol in the fuel system.
  4. To completely avoid the damaging effects of 'bad' petrol, it is best to run the fuel line and carburettor dry. If the engine has a fuel valve, turn it to the OFF position. If your engine does not have a fuel valve, you will have to remove the fuelpipe from the carburettor and plug it to prevent the contents on the tank from running out.
  5. Start and run the engine until it stops from the lack of fuel in the carburettor fuel bowl. Running time should be approximately 3 minutes.
The warranty does not cover fuel system damage resulting from neglected storage preparation.