Present two stroke engines used for hand held power tools must confirm to prevailing emission legislation. A fact is that today the engines have to be run at leaner air fuel setting resulting in less amount of lubrication oil passing through the engine. This lean mixture combined with high mixture trapping efficiency also affects the combustion, raising the overall working temperature of the engine. So to gain more robustness out of these air-cooled power heads one viable route is to use different coatings to take control of tribology and heat management within the two stroke power head.
In this paper a first discussion and description of the different coatings and their merits to the air cooled two stroke engine is conducted. Furthermore engine data for the test engine, in this case a 70cc professional chainsaw are presented. The outcome of engine dyno testing of the different coatings are presented and analyzed for further discussion.
Conclusion, there are positive effects on the two-stroke power head by introducing new advanced engine coatings, to achieve the most out of the coatings this must be taken into account during the first design of the engine. Also the economic impact on the final products has to be considered for market competitiveness.