Why the walnut shell granule?

Cleaning the motor with walnut shells? Sounds unusual, but the explanation is simple. A big advantage is that the granule is organic. So you do not need any chemical auxiliaries. The sharp-edged granule splinter clean the engine compartment without the risk of damages. After the blasting process the dry granule can exhausted without leaving any residue. Even though there are residues, the small particles are burned and exhausted from the engine.