Concentrated oil which reduces carbon capture on the valve and valve seat (valve heads and seats) the valve closed. It also helps with heat dissipation.
Head of engine oil which lower carbon stains that catch on the front of the valve and the valve (VALVE HEADS AND SEATS), the valve sealed and also helps distribute the heat.
The bacteria that reduce oil stains with soot and the handle on the valve valve's shoulder (VALVE HEADS AND SEATS) valve is closed, and it also helps to spread the heat.