Diesel Engines: Made Tough, Made to Repair

Diesel engines automatically put two images in your head when you think about what they represent; toughness and dollars. They’re made to last and made to work, but every driver realizes that diesel gasoline costs money to run and maintain. There are plenty of pros and cons for buying a vehicle that is a diesel, and thinking about what could potentially go wrong is an important part of making an educated, informed decision on what engine will work best for you. The development of diesel as a source of fuel goes back many years and has lasted throughout history to provide efficiency and strength and have grown into a popular choice for fuel power. In 1878, a man named Rudolf Diesel was studying in Germany at the Polytechnic High School, something similar to what we know to be an engineering college. During his studies, he learned about the low efficiency of gasoline (remember it was many years ago) and steam engines. The information was so shocking to him that he decided he needed to devote his time to develop an engine with higher efficiency and attempted Crankshaft Grinding to create a “combustion power engine,” or what we know today to be the diesel engine which he received a patent for in 1892.

Why do most cars have gasoline engines? Clearly diesels are not found in cars as frequently as gasoline engines are. According to auto experts, the 1970’s gave diesel engine popularity a little boost in sales due to an OPEC oil embargo. At that time, it was first used in cars during the oil crisis and people found their cars covered in soot. Although there are many pros to diesels which will be explained later on, many people find too many cons. First, they tend to be much heavier due to their higher compression ratios. They also tend to be more expensive than gasoline engines. This alone is important for most people to consider when choosing their perfect vehicle. Third, because of their weight and compression ratio mentioned above, diesel engines tend to have lower maximum RPM ranges than gasoline engines. This makes diesels high torque rather than high horsepower, and that usually seems to make diesel cars slower when it comes to acceleration speeds. Furthermore, diesel engines must be fuel injected, tend to produce smoke, and are described as “funny-smelling” by many observers. They can be harder to start in the cold winter weather, and if they happen to contain what are known as glow plugs, diesels can require you to wait momentarily before starting the engine so the glow plugs can heat up. Many people also notice that they are noisier, tend to vibrate more than gasoline engines, and in some areas diesel is less readily available than gasoline. This is a problem for people who drive diesel cars or trucks for work or in their everyday vehicles.

On the contrary, auto experts admit that diesel vehicles are quite efficient and have come a long way over the last several years. Many people wonder why there are not more vehicles with diesel engines if they have the important and modern description of “efficient.” There is still a negative image of diesel trucks that makes diesel engines seemingly less attractive to those who drive regular-sized cars. Diesel is perfect for hauling large shipments and heavy loads over long distances and in rugged terrain, but because of the size, weight, noise, and vibration, it isn’t normally the right choice for everyday commuters in smaller vehicles which may not be able to handle the engine itself. Engineers and auto experts are beginning to make diesel engines cleaner burning and less noisy to make it a bit more appealing to the everyday driver.

The emissions from burning diesel is one area that has improved tremendously over the years. When compared to emissions from unregulated engines 40 years ago, today’s on-highway diesel engines emit 99 percent less PM and NOx. According to one engine manufacturer, in 2010, all heavy-duty diesel engines sold in the United States had to meet the “NOx standard (0.20 grams per brake-horsepower hour (g/bhp-hr)) and the PM standard (0.01g/bhp-hr)” as set forth by the Environmental Protection Agency. These are the most stringent emissions regulations in the world according to experts and as manufacturers continue to create better, more universal diesel engines, it is good to know that they will have to continue to follow these same stringent regulations. If diesel fuel wasn’t efficient, it would not have stood up to being the main fuel used for transferring goods across the country. As mentioned previously, diesel fuel is heavier and oilier than gasoline is. While diesel engines tend to emit nitrogen compounds and particulate matter as they burn diesel fuel, it actually emits lower amounts of carbon monoxide, hydrocarbons and carbon dioxide than gasoline does. There are also new direct injection devices which are controlled by a type of computer which monitors the fuel combustion in the engine. This leads to better energy efficiency and fewer emissions. There are also other new devices on the market making diesel powered engines even better; catalytic converters and CRT filters of particles are reducing soot, carbon monoxide, and hydrocarbon emissions by almost 90% as stated by the Diesel Technology Forum.

Unfortunately, when it comes to diesel trucks and cars, there are many things that could go wrong. Because diesel engines are larger and slightly more intricate, it may cost more to repair at an auto repair shop. They still require regular maintenance to keep them running at optimal performance. You must change the oil itself, air, oil, and fuel filters. Although cleaner diesel fuels means you are no longer required to bleed excess water out of the system, many vehicles still have water separators that need to be manually emptied. Furthermore, when you neglect the regular maintenance of a diesel engine, the fuel system could break down. If this happens, a repair can cost more money for parts and labor than a traditional gasoline engine. Diesel powered engines are quite technologically advanced and because the technology is changing frequently,must stay trained on the advancements in order to properly repair the diesel engines. Not all mechanics continue this training and not all auto repair shops are able to repair or maintain diesel trucks. Part of making the decision as to whether or not you would consider a diesel engine must be whether or not you have a trusted mechanic who is capable of performing the tasks on the engine. Again, the government has put pressure recently on engine manufacturers to create low-emission diesel engines for passenger vehicles which are appealing. Not only could they be used with passenger vehicles, but also with trucks, buses, vans, and farm and construction equipment. This pressure is continually resulting in low-sulfur diesel fuels and newer, more advanced catalytic converters, advanced filters, and other devices which have the ability to cut down on toxic emissions.

According to diesel experts, diesel engine failure typically is the result of bad diesel fuel or lack of routine maintenance. The problems begin in the diesel engine itself, destined for diesel failure. Diesel fuel is unstable and solids will begin to form creating a sludge-like substance in the tank. It can eventually clog the diesel fuel filters, ruin the injectors, and even cause the engine to smoke. According to one company, “contaminant build-up is the result of excessive microbial growth and bio-degradation of diesel fuel can cause fuel filter plugging. Micro-organisms, bacteria and enzymes, fungus, yeast and mold cause diesel fuel degradation and lead to more significant diesel engine failures.” Knowing what you’re getting with a diesel engine is important. In the future, it may be an advanced engine for passenger vehicles and larger work or transfer vehicles. For now, it may be a little premature to run out and find a vehicle with a diesel engine.