Engines *can* explode, but it's easily avoidable since even the most basic gate has the power requested condition. If the power grid is saturated, the engines shut off. Still trying to figure out how to set up the proper conditions to prevent combustion engines from exploding.
Edit Again: Combustion engines seem to require gold gates to make them explosion proof, iron and gates cannot tell the difference between the fuel tank and the water tank.
Edit Again: Combustion engines seem to require gold gates to make them explosion proof, iron and gates cannot tell the difference between the fuel tank and the water tank.