Snobdds
Elite Member
I think you're not understanding the physics here. It's simple, if your have more air in a combustion chamber than fuel, it's going to burn hotter due to the higher percentage of a gas (oxygen) than a fluid. The opposite of supplying more fuel than air will make an engine run cooler.
The fluid, gas or diesel, can only be atomized by air introduced into a combustion chamber. It never turns into a gas or vapor.
If you want to understand it better, dive into the 2 stroke motor and how it works. People understood how the interaction of air and fuel upon a combustion chamber were linked going back to the 50's. In a 2 stroke, if you run lean...you burn up the piston and cylinder. So having the proper air/fuel mixture is critical. You quickly learn that too much air is what drives the heat.
In a diesel, the fuel delivery is handled by a vane pump in the older mechanical set ups. It runs off a lobe on the cam that drives the pump faster as the RPMs increase. It then delivers more fuel. So there is a direct relationship to always deliver the proper amount of fuel. In the common rail system, it uses throttle position or drive by wire, to tell the ECU to dump more fuel depending on load.
Diesels can run lean, but if your pump or sensors are working, it will never run lean. Also it's critical in a diesel to have good flow of diesel to make sure it dosen't run lean. That is why there are two fuel filters to make sure good fuel delivery. Diesels do however need heat for a proper combustion, to a point. If a diesel has a high duty cycle, meaning they are running full load for hours on end, then they will need a pretty robust cooling system. Like in my powerstroke, Ford had to use two radiators to increase the duty cycle to keep the heat in check. Otherwise the motor will derate (fuel being held back) and hold back the rpms to save the engine from overheating.
So again, study the two stroke motor and it will all make sense...
