Cold Weather – Fuel
In cold weather, fuel does not vaporize very well in the combustion chamber and this makes starting difficult.
Modern diesel engines designed for cold weather use a pre-heater or glow plugs. Glow plugs are heating elements that warm up the air that enters the engine. They work on a timed circuit or are manually activated just before the engine is started. The colder it gets, the longer those glow plugs need to stay on to preheat the combustion chamber for a smooth start.
Diesel fuel thickens in cold weather. It has a tendency to gel. Diesel Fuel has some naturally occurring paraffin (wax) and as the temperature drops, this paraffin crystallizes and affects the fluidity of the fuel and may cause hard starting and eventually lead to filter plugging. You can use a fuel additive to prevent this and is recommended for all year round use.
It is much better to store your coach with the fuel tank FULL. This minimizes condensation in the fuel tank. And having water condense in the fuel tank leads to all kinds of contamination issues.
Example: If you have a 100-gallon tank and drove 3/4 of that out early this fall (when you had high temperatures and high humidity in GA) you now have 25 gallons of fuel and 75 gallons of humid air– probably with a dew point of over 65 degrees F.
When the walls of the tank get below that temperature, water starts to condense and sinks to the bottom of the tank. When it gets down below freezing a LOT of moisture will condense in the tank.
Additionally, as the tank breathes (remember, there is a vent line, it is not sealed) air out during the day (hot air expands) and air in during the night, additional moisture is drawn in. To then condense… The few dollars you may save speculating on the price of diesel will appear very small if you end up with injector issues or algae growth in the diesel (the algae grows at the water/diesel interface).
Cold Weather – Batteries
Batteries that are weak may not crank the starter motor fast enough to start a cold engine. As the temperature goes down, so does battery capacity. A battery that has all of its power available at 80 degrees F will have only about 46% available power at 0 degrees F. Plus, the engine will be 2.5 times harder to start at 0 degrees due to thicker oil and resistance to movement of internal moving parts. In effect, an engine is about five times harder to start at 0 degrees F than at 80 degrees F. Test weak or suspicious batteries under load before cold weather to help eliminate potential problems during busy times. If batteries need replacement, always replace them with a battery equal to or more powerful than the original battery.
Keep your battery stored indoors to prevent it from freezing. Consider buying a small battery charger/maintainer to keep the battery topped up so it is always ready to use.
Cold Weather – Oil
The warmer the engine oil is, the thinner it will be and have less resistance to moving engine parts. Make sure you are using the proper viscosity oil recommended for your engine for cold temperatures. If you cannot store engines inside or in a heated area, consider installing a block heater on the engine. To save time and electricity, but the block heater on an electrical timer set to come on a couple of hours before you plan to start the generator.
After starting the generator on a cold day, allow the engine to warm up a few minutes before putting it under load. Proper engine operation temperatures assure more efficient fuel combustion and may prevent damage to cold engine parts. Engine oil flows more readily at operating temperatures and allows proper lubrication of engine parts and areas.