How does 'running lean' damage an engine?

Question

How does 'running lean' damage an engine?

Answer 1

Running lean makes the engine run hot. This tends to lead to 'pinging'/'knocking', or preignition. This causes greatly increased cylinder pressures and heat, and can hammer bearings, crack piston rings/ring lands, burn pistons and valves, bend/break conrods, the list goes on...

Answer 2

You engine can suffer from engine knock (engine fuel detonation). That is how your engine destroys itself from inside out.

Piston parts are literally blown to pieces.

http://en.wikipedia.org/wiki/Engine_knoc...

Good Luck....