At what degree does diesel fuel freeze?

Question

i was just wondering at what degree does diesel fuel freeze at because my mom drives a school bus for a living and when she got home she told me her fuel was frozen this monring and we live in CT

Answer 1

I drove a bus for many years and I think it is at about 0 - 10 farenhite. cold burr

Answer 2

at 32 starts to cloud up at 15 starts to gel

Answer 3

Depends on the anti-gelling additivites that have been added to the fuel.

"Unreated" diesel begins to gel and seperate just below freezing point. Additives can take that temperature far lower. But additives cost money, which increases the cost of the diesel.

So the lesson is  - do not buy cheap diesel in winter - it might have insufficent additives and seperate as the temperature drops. The cost of repairing the engine after seperation has taken place is prohibiative

Answer 4

It depends on the actual makeup of the diesel fuel being used, and the actual composition of any given fuel varies depending upon source of the crude oil, refinery processes, and product specifications.  Diesel fuel has many additives depending on application, temperature at point of destination, etc.  One type of additive is a 'cold flow improver' to lower the point at which paraffin crystals in the fuel will clog the fuel filter.  The filter will clog because of this or water in the fuel will crystallize before the fuel freezes completely.  Either way vehicle operation is effected.