At 34°F, you begin to see the start of the gelling process and fuel starts to get cloudy. By 15°F, it gets worse and full on gelling has got you, which will block filters and stop you on the spot.
To avoid diesel fuel from gelling is to use an anti-gel fuel additive. Anti-gels drop the cloud/freezing point of diesel fuel.
Trust me, water is going to magically appear in the fuel by either, poor storage, handling, and condensation in the tank.
In the winter, fuel will gel but water in the fuel will freeze at 32°F and begin problems with fuel lines and water separators.
So at the bare minimum do one thing… GET THE WATER OUT.
No water means no water to freeze and break something.
Here is the quickest and simplest little device to get the water out.
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