LOCKWASHER 5W7027 - Caterpillar

3406E Truck EnginesThe only appropriate materials to use for cleaning the 7E-0525, 108-2716, and 117-5063 Piston Body Assemblies are liquid detergent, hot water, and a non-metallic brush. Specifically, use a liquid detergent with little or no chlorine. A common example is the brand name detergent "Wisk".
The proper cleaning method is to mix 250 ml (8.5 fl oz) of liquid detergent with 8 L (2.1 gal U.S.) of hot water. (This is a 32:1 ratio of hot water to liquid detergent.) Place the piston into the solution until the carbon and oil deposits have loosened. One to two hours is usually sufficient. To reduce cleaning time, heat the detergent and water solution to a temperature of about 55°C (130°F).
Leaving the piston in the solution too long may cause the aluminum to darken in color.Scrub the piston with a non-metallic brush in order to remove deposits. Use special care in order to prevent scratches in the ring grooves. Scratches will increase blowby and oil consumption.
It is not recommended to glass bead any part of the piston. Do not reuse the piston if it has already been glass beaded.