On Fri, 14 Nov 2008 09:19:59 -0800 (PST), Capt John
wrote:

rong, wrong, wrong. You can run a diesel lean, when you have a
restricted fuel system

Lean or rich describes fuel air mixtures, and Diesels don't even have
them.
Even so, lean lowers the temp.So does rich. Airplanes have a mixture
control and if you have an EGT gauge, it is easy to see it in action.
Lower temperatures on both the rich and lean sides of a peak. Lean,
you have less fuel heating the same ammount of air. This raises the
temperature how? It doesn't.

Casady