Eli5: Why are petrol engines not built like diesel engines in terms of reliability?

Question

Diesel engines easily run 400.000km especially Mercedes cars but petrol will give up way sooner

In: Engineering

Answer 1

Diesel engines being built “stronger” means the parts in the engine that move around a lot, weigh more. This limits RPM which is less of an issue with diesel engines because diesel fuel generates more power per unit of fuel than gas. So diesels can rev lower and still make plenty of power. The higher reciprocating mass also generates more torque (the actual, measureable work) at lower RPM.