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Four advantages of a diesel engine over a gasoline engine:

Efficiency: They burn less fuel to generate a given amount of horsepower. They are 20 - 30% more efficient than a gas engine.

Engine Durability: Because a diesel engine must be built heavier to withstand the pressure within the engine, it can be expected to run many hours longer than its gas counterpart.

More Lugging Power: Torque rise under load is an inherent characteristic of diesel engines.

Less Pollution: The exhaust from a diesel engine, although more visible at times, contains low levels of toxic elements harmful to people. What you do see in diesel smoke are particulates, carbon and soot.

Name three differences between a gas and a diesel engine:

Type of fuel it uses: Diesel fuel is a less volatile fuel than gasoline but possesses a greater number of BTU's per gallon. As a result, more total horsepower is obtained from a gallon of diesel than a gallon of gas.

Type of Ignition: The fuel and air mixture in a gas cylinder is ignited by a spark. In a diesel engine, the mixture is ignited by the heat from compression.

Fuel and air mixing: In a gas engine, the fuel and air mix takes place in the carburetor and the intake manifold and the fuel is ignited by a spark plug. In a diesel engine the diesel fuel is mixed with compressed air when the fuel is injected into the cylinder. Because air heats up when it's compressed, the fuel ignites.

Why are diesel trucks harder to start when it's cold than a gasoline truck?

The fuel is ignited using compressed air that is hot. When it's cold out, it takes longer for the temperature to rise. The cylinders take longer to heat up as well. Some engines have glow plugs or intake heaters to assist in creating heat to improve cold starts.

Diesel fuel gets thicker when it's cold, there is more contamination in diesel fuel and it can actually freeze.

What can be done to improve the starting and run ability of my diesel truck during cold spells?

Before the cold season, have the glow plugs or intake heater checked for proper operation.

Have the block heater checked for proper operation and plug in the truck whenever feasible.

Treat the fuel in the tank with a diesel fuel supplement that prevents gelling and boosts Cetane. Even treated fuel from the pump is not enough for severe cold.

Assure the truck batteries are good and the charging system is working.

Start with a fresh fuel filter and replace fuel filters often.

Why are oil changes so much more important to your diesel engine than the gas one?

The primary purpose of engine oil in a gas engine is lubrication. Oil in the diesel engine not only lubricates, but it cools the engine and cleans the carbon away from the pistons and the liners. The key to diesel engine longevity is oil changes every 3000 miles on the nose!

Why are fuel filter changes so much more important for a diesel engine than a gas engine?

The fuel filter in a diesel engine separates water out of the diesel fuel. Excessive build-up of water in the filter can cause freezing in the fuel system, can cause the vehicle to be hard to start, to die-in-flight or run poorly. It is recommended that the fuel filter be changed every 6,000 miles (every other oil change). In the winter when the temperatures are low, the filter should be changed every oil change. This will help prevent fuel jelling.

What other maintenance items should be done periodically?

A valve adjustment, also known as an "overhead" should be done every 60,000 miles on some engines to assure maximum performance.




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