Swissvax Engine is a concentrated detergent, and should thus be diluted to an appropriate strength in a Swissvax Mixing Bottle before use. For normal cleaning, a dilution ratio of 2:1 (water:product) is often sufficient, but this can be reduced to 1:1 for tackling really old neglected surfaces. In all cases, an appropriately diluted solution should be sprayed on directly and then agitated thoroughly using a Swissvax Detail Brush. This will produce a rich foaming lather, which will quickly discolour as dirt and grime is progressively released. Accordingly, it is sensible to rinse out your brush regularly during this process, otherwise there is risk of marring sensitive surfaces. The lather should then be rinsed away thoroughly with an open ended hose and the engine dried fully before any protective products are applied.