If you've always driven a petrol-powered car and are considering switching to something with a diesel engine, it's best to find out some basic information about how diesels work. The following information may help.

Fuel Efficiency

Diesel fuel is more efficient than petrol. It is denser, has more useable energy and gives you more kilometres per tank.

But, a diesel-fuelled car is not designed for fast race car starts. If you like to step on the accelerator and have an instant response, diesel may not be for you. Think of petrol-powered cars as racehorses. They are flashy and leave the gate as soon as the barrier is thrown. Your diesel engine acts more like a Clydesdale—slower, steadier and able to work for longer periods without tiring. That said, the addition of turbochargers and computer components on some modern diesel engines have made that Clydesdale a bit more energetic.

Maintenance Differences

Petrol-powered cars have sparks plugs and distributors that need changed regularly. Diesel engines have glow plugs. These are heating elements that trigger the start of the engine. Their longevity is determined by climate, the amount of use and the overall condition of the engine. As far as the climate factor goes, the colder it is, the more the glow plugs have to work to start the engine.

Diesel engines also have different maintenance needs. The oil should be changed every 5,000 kilometres and the oil filter every 10,000 kilometres. The fuel filter needs to be checked and cleaned periodically. Just how often depends on the quality of diesel you're using. Most diesel engines have water separators that need to be emptied. Water separators extract molecules of water from the diesel. With the cleaner diesel fuels of today, the water issue isn't as big as it once was.

Engine Longevity

With proper maintenance, a diesel engine can last between 350,000 and 500,000 kilometres. The maximum on a petrol engine tops out at between 250,000 to 300,000 kilometres. Vehicles that reach these upper numbers are well maintained.

Off-Road Differences

Diesel engines are preferred by those who live or spend considerable time in the outback. Diesel fuel is usually more prevalent than petrol in these areas. Since diesel engines produce more torque, they have more power to get out of sticky situations, like pulling out of a steep ravine. All wheel drive vehicles with diesel engines also use that power to more easily haul caravans and other equipment.  

Petrol-powered cars have a couple of pluses worth mentioning. When you can find petrol, it is usually less expensive than diesel in the outback. The quick response also makes it easier for petrol-powered cars to pass road trains and other slower vehicles you might encounter. For more information as you make your decision, talk to an experience mechanic, such as B & M Fuel Injection Pty Ltd.