About 1888, DIESEL invented the Diesel engine upon the principle that ignition could be obtained by pressure in a cylinder, thus igniting heavier fuels than the then used naptha in "gasoline" engines.
The first use of Diesel engines was in ships and railway engines. Then the company that we know now as Mercedes-Benz experimented with trucks using that engine.

But it was 1923 before any manufacturer came out with a Diesel personal car for a consumer...that car manufacturer was Peugeot of France.

Other car manufacturers followed but only the Scandinavian and Germans continued regular lines of Diesel cars. Mercedes-Benz with the 170-D in 1937 started a series that has continued to today.

When compared with gasoline powered vehicles, DIESEL shows both advantages and disadvanages.
The advantage is that on a per gallon of fuel basis, foot-pounds of work achieved by Diesel is about one-third (33%) more efficent. But the advantage to the oil companies is that the preparation of diesel fuel from crude oil is simpler and cheaper than the production of high octane gasoline.

The money difficulty involved is that the engines required for diesel fuel operate at a much higher pound per square inch ratio than gasoline engines, thus requiring heavier and better metals for their cyinders, etc.

Until recently, diesel engines in cars produced much more violation of the atmosphere than gasoline cars, but that is presently regulated by emission controls, most through a platinum coated exit valve.

The advantages of diesel engines are somewhat offset by their need to 'warm up' before getting to full engine power...the more modern Mercedes have overcome that problem to an extent by complicated jet-plus-air controls.

In the present oil crisis, the advantage of the Diesel engine is that it can very easily be converted to use vegetable based oils, which not only give an approximate of the usual power, but emit gasses that are not polluting like regualr diesel fuel.

If one puts the cost of a Diesel limousine (this writer's 300SD Mercedes cost $41,150 originally) there is no money advantage to using diesel fuel as one has a large initial purchase price to overcome.

But a plus factor is that diesel cars rapidly drop in value and a $40,000 car five or six years old can be purchased used for about $2500. Using such a purchase converted to vegetable oil, and obtaining vegetable oil at about $2 a gallon would give an advantage to the owner.

The main disadvantage in diesel cars is their balking in colder weather. In areas where the temperature remains below freezing, it is necessary to preheat the engines (usually with a built in heater) which adds to the complications.

All in all, though diesels are reliable and long-lived (this wrter's last one was traded in at 770,000 miles) the truth is money-wise one ends with an equal situation versus ordinary small gasoline powered cars.

Learn more about this author, William Cobbs.
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