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5 Things To Help Combat and Cure A Cold Cummins

Posted in How To: Engine on September 30, 2016
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When the temperature dips to the bottom of the needle, diesel fuel transforms into a consistency resembling molasses, leaving the wax particles within the fuel and thickening or “gelling” inside the arteries of the truck clogging. And just like cholesterol clogs human arteries, gelled diesel fuel in your truck’s fuel system is like a heart attack waiting to happen. Most diesel fuels can withstand 32 degrees. For most of us, we know it often gets much colder than that! Here are five easy ways we’ve found to help defend your Cummins against the evil freezing arctic temperatures.

1. Fuel Additive: This simple solution should always be running in the veins of your 4x4 at all times during cold months. As an added bonus, they contain cleaners to help remove deposits that are built up within your fuel system, as well as additives to combat the gelling process in colder temperatures. In short, it prevents the paraffin wax found in diesel fuel from thickening. Diesel fuel additives usually have a cetane booster that helps with faster start up times. Cetane is the measurement of delayed ignition of the diesel fuel represented by a number. Most U.S. filling stations have diesel fuel with a Cetane rate of 45. Increasing Cetane levels in your diesel fuel will help with faster ignition times for your diesel engine.

2. Batteries: Long starts drain the batteries in colder conditions. You'll find two batteries in parallel maximize the cranking amps (CA) needed to spin your diesel engine and ignite the air/fuel mixture. When purchasing your next battery, look for a rating of cold cranking amps (CCA). This measurement is found on the battery and is a measurement based on 30 seconds of starting while holding at least 7.2 V. The minimum need for most diesel engines is around 750 CCA.

3. Engine Preheater: Your Cummins engine doesn't come with glow plugs. It's equipped with a grid heater that uses electrical current in a heating element that is shaped like a grid. This maximizes surface area warming the air to be drawn through the engine block for ignition. As soon as the key is turned to the On position, the heater then will heat the grid. Once it reaches the set temperature, your dash light will turn off letting you know it’s time to turn your key over to the On position.

4. Coolant: Sometimes when a low coolant warning shows up, some of us just add water that's nearby for a simple solution. This isn't always a bad thing since most antifreeze mixes are 50/50 coolant and water mix. Unfortunately, water will start to crystalize to ice when the temperature falls to 32 degrees. This can lead to cracked blocks, lines, and radiators. On the other end, most antifreeze manufactures recommend not going more than 70 percent coolant mix to help keep the heat transfer and other benefits, like freeze/boilover ratings, optimal. So before the freezing season starts, it's a good time to perform a coolant flush so you have the right mix going into the cold season.

5. Oil: This fluid doesn't seem like it plays a role in the help of starting your diesel, but in reality, it does have a dramatic effect since so many rotating engine parts are submersed in it. The term viscosity is the measurement of fluid while drawing the fluid through a device known as a viscometer. It's then labeled with the correct weight rating. For example, with 10W-40, the first number is the viscosity of the oil when the oil is cold. The "W" means it has been tested at colder temperatures, or winter rated. In this case, the 40 is known as the thickness when the oil becomes warm. The thicker the oil in colder environments, the harder the oil is to flow, leaving more resistance on internal parts on the engine and creating more drag, especially when starting.

Adding Royal Purple Max-Tane fuel additive to your Ram’s fuel tank will give a Cetane boost of 8. We mix 1 ounce of Max-Tane to every 2 gallons of diesel fuel for max performance.
On the far right of the Optima battery label you'll find the battery ratings. CA stands for cranking amps and CCA is the cold cranking amps rating. A minimum of 750 CCA is recommended for diesel applications.
The grid heater can malfunction or the elements get coated in soot, reducing their effectiveness. If it needs replacement or cleaning, you can get to the Cummins grid heater by removing the four bolts on the intake and the oil dipstick. Behind the intake there is one somewhat-hidden bolt on the intake that will need to be removed to take your intake off.
Two bolts that have the electrical source to the grid heater will need to be loosened for the last step of the removal process.
When finished with removing the intake grid heater, it’s a good idea to stick a vacuum hose down the intake to remove any loose debris that may have fallen in before installing the new part.
After placing the grid heater gasket on, you can put two bolts in the grid heater to help it stay in place to tighten the two electrical connections on the rear of the grid heater. Then remove the bolts to lay the second gasket between the grid heater and intake. Tighten remaining bolts and you’re finished.
After draining the entire radiator from the lower petcock, we added a bottle of Royal Flush then topped it off with water to let it run for 15 minutes with the heater on High to circulate all coolant lines. After the engine is cooled down, drain the system and then repeat topping off with water to let it run another 15 minutes. Once the engine is cool, drain the radiator and you’ll see containments flowing out of your system.
With the proper ratio of coolant and water established, we then topped off our coolant system with a bottle of Royal Ice coolant additive to help condition the radiator.
Royal Purple 10W-40 is our choice for our Cummins engine this winter. In warmer weather we’ll swap out to 15W-40. Remember almost 3 gallons of oil is needed after the filter change to fill your Cummins back up.


Royal Purple
Porter, TX 77365
Optima Batteries
Milwaukee, WI 53209

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