Cummins qsb3.9 engine is with a small efficiency loss is also avoided compared to two-stroke non-direct-injection gasoline engines since unburned fuel is not present at valve overlap and therefore no fuel goes directly from the intake/injection to the exhaust. Low-speed diesel engines (as used in ships and other applications where overall engine weight is relatively unimportant) can have a thermal efficiency that exceeds 50%. 

 Cummins QSB3.9 diesel engine is widely used for forklifts, millers, rollers, graders, mini excavators, etc.

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