11 strategies to help your diesel engine in cold weather conditions

Tier III & IV high pressure common rail (HCPR) fuel systems have been a true benefit for engines over the past 10 years by improving engine performance through more efficient combustion.

HCPR fuel systems optimise fuel consumption and reduces particulate emissions.

However some new equipment owners have experienced fuel related downtime and/or operability issues in colder weather conditions.

Around 95% of the particulate typically found in diesel fuel was not a problem for older engines but new HCPR engines must be protected from all of those particles through highly efficient filtration.

Fuel handling practices from past are usually insufficient to maintain reliable cold weather operation for new equipment with HCPR fuel systems.

Check out these strategies from Donaldson for operating modern diesel engines in cold weather:

1. Use the cloud point

This is the temperature at which fuel becomes hazy as your key indicator on how well your fuel will operate in cold conditions. The fuel itself begins to form filter plugging solids at about -15° C / 5° F above the natural cloud point.

2. Misunderstanding the Cold Filter Plugging Point

Don’t be fooled by the Cold Filter Plugging Point (CFPP). CFPP is not intended to determine if fuel will pass through the filter on a modern HPCR fuel system; it was historically intended to indicate if gelled fuel can pass through a coarse screen protecting the fuel dispenser pump.

3. Supply

Have a discussion with your fuel supplier to determine what blend of #1 (winter) and #2 (summer) fuel you need for the next two weeks of operation.

4. Purchase fuel in quantities

Don’t purchase fuel in the fall and expect it work in January. Try to purchase only enough diesel for 2-3 weeks of operation. The further below the cloud point fuel gets, the more solids form that will likely plug filters.

5. Housekeeping is key

Make sure your tank is free of water, sediment and microbes. Find a professional fuel tank cleaner. If tank cleaning is done improperly, it can cause more issues than it fixes. Water makes solids (ice crystals) in winter that plug filters. Full fuel tanks are less likely to form water.

6. Use cold flow additives 

If additional cold weather operability is required beyond your blend of #1 (winter) and #2 (summer) fuel, use cold flow additive sparingly to reach an acceptable cloud point for that week’s weather. Never add cold flow improver to cold fuel or add more than manufacturer recommended. Try not to splash blend cold flow additive if at all possible.

7. Reduce condensation build up

Top-off / fill your vehicle’s fuel tank at the end of the shift while it is still warm. This limits water condensation buildup in tanks.

8. Never switch to lower filtration efficiency

Never switch to a more open (lower filtration efficiency) on-engine fuel filter with a modern HPCR system. If waxing is expected, take the fuel filters off the truck and move indoors for approximately 20 minutes – the wax should melt. If it doesn’t melt, then you are experiencing a fuel chemistry filter plugging issue.

9. Bio blends don’t perform in cold weather

If you live in an area where biodiesel is not mandated, don’t use it in the winter months if possible. Bio-blends have poor cold weather performance compared to #1 and #2 fuel. At 5% blend or less, biodiesel is considered a lubricity additive and often not identified.

10. Keep spares

 Keep an extra set of on-engine fuel filters in the equipment or vehicle’s cab.

11. Use the correct filter

A general rule is to use a filter with the same micron and beta rating at the dispenser as your secondary on-engine fuel filter. However, in winter months the single pass winter fuel filter (DBB8777) on your storage tank can be used to maintain flow. This will ensure that any likely fuel quality issues are captured before the fuel enters the engine.

Article Credit: Donaldson