Walnut shell blasting media (Figure 1) offers a number of benefits. For instance, it is non-toxic, environmentally friendly, and hence does not pose any health or environmental hazards.

This video shows the footage of Walnut Shell Blasting at the Norfolk Navy shipyard from Composition Materials. Ted Diamond of Composition Materials Co. explains how walnut shells blasting of Navy ...

The process of walnut blasting, which entails cleaning the intake manifold and valves of a car’s engine with a high pressure air blast of finely crushed walnut shells (a biodegradable abrasive), ...

Finely crushed walnut shells are used as the blasting media, and they are safe for virtually all metals. The shells are also environmentally safe, and no chemical cleanup is required.

Walnut shell-blasting is very popular because the media is soft, relatively easy to clean up, and is not abrasive after the blasting is completed.

The walnut shell blaster is used once the intake manifold is removed to blast off any deposits. I first heard about walnut shell blasting to clean carbon buildup in aircraft engines.

Walnut blasting a good—if expensive, as the intake manifold has to come off—way to maintain engine performance for the life of a direct-injection car.