Why You Should Choose Small Diesel Engine

The major distinction between diesel and gas lies in the type of ignition. While gas engines operate on spark ignition, diesel engines (including small diesel engines) employ compression ignition for igniting the fuel. With compression, the air is drawn into the engine and subjected to high compression that heats it up. The result is a very high temperature in the engine, much high than that of gas engines.

In small diesel engines, air and fuel are both infused into the engine at different stages, as opposed to gas where a mixture of air and gas are introduced. The fuel is injected into the diesel using an injector where in a gas engine, a carburetor is used for this very purpose.

With gas engines, fuel and air are sent into the engine at the same time, then compressed. The air and fuel mixture will limit fuel compression, and thereby hence the overall efficiency. Small diesel engines only compress air, and the resulting ratio can be much higher.

Advantages
Small diesel engines are much more efficient and preferable as compared to gas engines due to the following reasons:

1. Small diesel engines have overcome the several disadvantages of earlier models that featured higher noise and maintenance costs. Now, they are quiet and require less regular maintenance when compared with gas engines of a similar size.
2. Small diesel engines are more rugged and reliable.
3. There is no sparking at all as the fuel ignites. The absence of spark plubs or sparkwires also helps to lower maintenance cost.
4. The fuel cost produced is 30 - 50 percent lower than gas engine fuel prices.
5. Gas burns hotter than diesel, and therefore they have a shorter life span when they are compared with small diesel engines.

Why People Use Small Diesel Engine

With small diesel engines, the compression ratio is higher and there is more power. From a technical point, the compression ratio of a small diesel engine is the comparison of the total volume of the cylinder at the bottom of the piston's stroke divided by the volume of the cylinder remaining at the top of the stroke.

Gasoline ratios
Serious damage to gas engines can occur if you attempt to run a high compression ratio with a low octane type of fuel. Detonation is the ignition of the fuel due to the high temperature caused by a high compression ratio that is developed by design. The fuel is ignited prior to the spark of the plugs that result in a rapid, yet uncontrolled burning.

Diesel ratios
Keep in mind, the small diesel engine is a heat engine, using heat developed from the compression of air. High compression ratios are possible since the air is compressed. The hot compressed air is sufficient to ignite the diesel fuel when it's finally injected near the top of the compression stroke.

Diesel engines
Fuel and air in the design of small diesel engines are not premixed outside of the cylinder. Air is taken into the cylinder through the intake valve and then compressed to make heat. The diesel fuel is injected near the top of the piston's stroke in an amount or ratio that corresponds to the load on the engine.

Heavy duty
The higher compression ratio causes engineers to design, and test the block, heads, head bolts,
crackshaft, connecting rods, rod bolts, pistons, piston pins, etc., with a greater range of structural
capacity. To put it in other terms, diesels engines are heavier than gasoline engines.

Gasoline
Deciding on gas and diesel can be tough, although there are several reasons why you should use diesel.

1. Diesel engines produce twice the power per gallon of fuel than gasoline.
2. A gallon of diesel is normally cheaper than a gallon of gas.
3. Diesel fuel doesn't blow up. The fact is, its hard to get diesel to burn at all.
4. Diesel engines (including small diesel engines) will last four times longer than gasoline engines.
5. Diesel fuel that is untreated will last longer in storage than untreated gasoline.
6. Treated diesel fuel will last longer in storage than treated gasoline.
7. Diesel fuel treatment will cost less than gas treatment.
8. Spoiled diesel can be reconditioned to refinery specifications, as spoiled gas can't.
9. Unmodified small diesel engines can be ran on vegetable oil.

How Small Diesel Engines Work

When gas is compressed, the temperature of it will rise, with small diesel engines using this very property to ignite the fuel. Air is then drawn into the cylinder and compressed by the rising piston at a much high compression ratio than gas engines, up to 25:1, with the air temperature reaching 700 - 900 degrees C.

At the top of the piston stroke, the diesel fuel is injected into the combustion chamber at high pressure, then through an atomizing nozzle, it mixes with the hot high pressured air. The resulting mixture will ignite and burn very rapidly. This combustion will cause the gas in the chamber to heat up rapidly, which increases the pressure and forces the piston downwards.

The connecting rod will transmit this motion to the crankshaft. The scavenging of the engine is either done by ports or valves. To get the most out of a small diesel engine, using a turbocharger to compress the intake of air is vital. You can also use an aftercooler or intercooler to cool the intake air after compression by the turbocharger to further increase your efficiency.

An important part of older small diesel engines was the govenor, which limited the speed of the engine by controlling the rate of fuel that was delivered. Unlike gas engines, the air that comes in is not throttled, so the engine would overspeed if this wasn't done. Older style injection systems were driven by a gear system that came from the engine.

The small diesel engine is truly an advancement to vehicles as we know it. As technology gets better, you can expect small diesel engine to get better as well, possibly even proving just how much better it is to the gasoline engine.

General Information On Small Diesel Engines

Small diesel engines offer the lowest specific fuel usage of any other large internal combustion engine. The fact remains, two-stroke diesels with high pressure forced induction, particularly turbo charging, make up a large percentage of the small diesel engines.

Throughout North America, small diesel engines are generally used in trucks, where the low stress, high efficiency cycle will lead to a much longer engine life and lower costs to operate. These advantages also help to make the diesel engine ideal for use in the heavy haul industry.

Cars however, continue to use gasoline, primarily due to the consumer desire for a wider range of
RPM. In Europe, the use of small diesel engines with cars is far more common.

Even though small diesel engines are more efficient when throttled down, they aren't suitable for most types of aircraft. The higher compression ratios of the diesel cycle demand a much stronger block, head, and almost all moving parts in general. These stronger parts add a lot of weight, or a lot of expense, especially if lighter alloys are being used.

The Otto cycle engines are much cheaper to build for these reasons, although they have long been overtaken by the turbine engines. For the same displacement of the engine, Otto cycles will produce more actual power than a Diesel cycle can, because the fuel will burn at a much faster rate, allowing more power strokes per minute than a standard diesel can offer.

What this means, is that less fuel has to be carried. Additionally, commercial aircraft is normally run at preset limits, so that Otto cycle engines used in aircraft don't suffer anywhere near the efficiency penalties that land vehicles do. Heavy equipment, such as those used in mining and construction, almost always uses small diesel engines.

Small diesel engines are also used with submarines. In these types of submarines, the diesel engine is run when the submarine is on the surface, which charges the batteries that power the submarine once it is submerged.

All across the world, small diesel engines serve many different purposes. They are used with almost all types of heavy machinery, and other vehicles. Gas isn't the way to go with heavy machinery, as the engines simply can't withstand the beating.

Diesel has been popular for many years with machinery and submarines, simply because the engines can last for years and years. Although they won't offer as much speed as gasoline, the torque and power is still there.

Advantages Of Small Diesel Engine

If you've owned a diesel powered vehicle in the past or if you own one now, you no doubt appreciate the qualities small diesel engine provides you with. More torque, better fuel economy, and easier maintenance are but a few of the attributes of owning diesel powered vehicles.

However, there are some motorists that still complain about the engine's weak power, especially
when accelerating from a full stop. What you may not be aware of is the fact that a small diesel engine can be tweaked to give more power without harming the fuel economy.

Small diesel engines use air compression to create combustion versus the fuel/air mixture that is
required by gas engines. This attribute means that small diesel engines don't require spark plugs
and therefore don't need to be tuned up.

Diesel fuel has a much high fuel density than gas, which results in fuel economy increases
of 20 - 30% over gasoline powered vehicles.

Small diesel engines are also cheaper to maintain as they have less parts than that of a gasoline
powered engine. The life span of a small diesel engine is also much longer.

If you're looking for torque, for pulling a boat or other equipment, then the small diesel
engine has the supreme advantage. Small diesel engines are surely slower, especially when
starting from a dead stop, although when you climb hills or go over bridges, the small diesel
engine is surely up to the task.

With trucks, diesel is normally the leader over gas engines in terms of performance and
miles per gallon. Diesel trucks will get more miles than gas trucks, and the price for
diesel is a bit cheaper than gas these days. And with gas prices on the rise, diesel will
continue to dominate for a long time to come.