Direct injected cars have one major drawback over port-injected engines, which is that carbon deposits can build up over time, requiring them to be removed at regular intervals throughout the lifespan of the engine. The most effective and common method to do this is the use of Walnut Shells in a process commonly known as Walnut Blasting. Walnut blasting is when crushed up walnut shells are blown into the car’s engine with an air compressor. It works like a sand blaster removing the carbon deposits from the surface being blasted.

Walnut blasting is recognised by most mechanics as one of the safest and most efficient methods of removing carbon deposits from your car’s intake manifold and intake valves. Almost all direct-injected engines will require this de-carbonisation process completed at regular intervals during the lifespan of the car’s engine.

Walnuts are pre-ground, cleaned, and the membrane and fat are removed from the shell before they go for further processing. They are specifically ground on hammer and roller mills to get the correct size and surface of the granule. Walnut Shells are ground to various sizes (coarse and fine) for the use in a variety of applications. Walnut Shells are used in a similar manner to other blast media and can be used for more than removing carbon build-up in engines.

Whilst chemicals can be used to remove carbon, the process is generally more time consuming, more expensive, and less environmentally friendly due to the need to responsibly dispose of the cleaning chemicals used.

The process of carbon cleaning utilising walnut blasting is carried out by using crushed walnut shells propelled by compressed air to ‘chip away’ at the carbon build-up on the engine’s components. Relatively speaking, the walnuts shells are softer than the metal of the intake manifold and valves, so they won’t cause any damage to the engine but at the same time being hard enough to remove the carbon deposits that have accumulated.

    The advantages of using walnut shells for the blasting process include:
  • • Walnut Shells are environmentally friendly, natural, and non-toxic.
  • • Using Walnut Shells does not produce dust and they are safe for indoor use.
  • • Walnut Shells cause no health or environmental hazards in their usage.
  • • They are long-lasting, re-usable and biodegradable.
  • • Surfaces blasted with Walnut Shells require no drying time.

At Eden Products we supply Walnut Shell solutions to many industrial and pet applications. The preferred and only grade which can be used for carbon cleaning is our Walnut Shell WSG16.30. If you require any more information on our range of different granules or flours, please contact us and we will be more than happy to help

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