Maybe it has nevertheless still a chance. Of course, not as the completely outdated two-stroke engine with crossflow scavenging, as it will be shown almost everywhere in the web (video 1 below). Although, the question of purging no longer seems so important because, as you can see above in the small animation, fuel is only injected when the outlet channel is closed.

A two-stroke engine with direct fuel injection therefore retains its piston controlling of the channels and has no valves such as the big marine diesel. And nevertheless its exhaust gases are much cleaner than similar engines with carburettor. And because no scavenging losses are present, the already higher power output per liter displacement can be increased considerably compared to the four-stroke engine.

It goes even further, because a two-cylinder engine runs as a two-stroke engine with opposite acting piston, what its mass balance significantly improves. Yes, even the oil in the exhaust gas could be eliminated by charging, because then an oil sump would be possible. The more expensive injection system is the only drawback, which generates pressures from 50 to 200 bar.

This technique is available e.g. from Orbital. Here is even realised a kind of stratified charge because aware only in the vicinity of the spark plug is produced a slightly richer mixture. Instead of pure fuel, an air-fuel mixture is injected, what reminds of the first diesel engine. The engine is virtually indistinguishable from a conventional two-strokes except on its injection valves .

Even the fresh oil lubrication was maintained, but very finely dosed electronically, according to the manufacturer down to 1: 400. That would correspond in case of 5 litres oil to change and 6 to 7 litres fuel consumption per 100 km an oil change approximately every 30.000 km. However, slowly, the stated value is achieved only at idle speed. Because the fresh oil lubrication only little oil supplies the fuel, however, targeted a lot of to lubrication points, for pressure lubrication it lacks only the oil collection system in principle.

The company Ficht works with the injection of pure fuel and uses the movement behaviour of a solid, in order to increase the injection pressure and thereby to improve the atomization of the fuel. The company uses now the help of much larger partners and supplies eg with outboard engines Kawasaki, Polaris and Evinrude. The original Ficht system is explained below in Video 2.

Also Orbital is active in the marine sector. Wherever it affects small and lightweight versions of internal combustion engines, such a system has a chance, for example, even at snowmobiles. One gets now 100 kW from a three-cylinder with almost 1100 cc for a Kawasaki JetSki. Perhaps the two-stroke engine with direct injection appears still as a range extender in the transitional period to the pure electric car. 11/15