How does a Tractor Engine Work? Different Types of Tractor Engines

Table of Contents

• What is the Role of a Tractor Engine?
• What are the Different Parts of Tractor Engine?
  • Cylinder
  • Piston
  • Camshaft
  • Crankshaft
  • Fuel Injector
  • Flywheel
• How Does a Tractor Engine Work?
  • Intake Stroke
  • Compression Stroke
  • Power Stroke
  • Exhaust Stroke
• What are the Different Types of Tractor Engines?
  • Naturally Aspirated Tractor Engine
  • Turbocharged Tractor Engine
• Tractor Engines by Fuel Type

What is the Role of a Tractor Engine?

Engine is the heart of any vehicle. A tractor engine generates power, which is transmitted to the PTO and wheels through the transmission system. Thus, it provides power to the tractor to perform all kinds of tasks on and off the road.

The tractor engines’ performance and design can vary depending on the type of work it is meant to do. For example, smaller engines are used for light tasks like gardening, while larger engines are used for heavy farm work.

What are the Different Parts of a Tractor Engine?

A tractor engine has a complex structure and comprises several parts. The key parts of a tractor engine are listed below:

Cylinder

It is a chamber where fuel combustion occurs to produce power. More cylinders mean more pistons to combust fuel, thus producing more power. The cylinder handles all the pressure and heat generated during fuel combustion.

Piston

A cylinder houses a piston that undergoes reciprocating motion to compress the fuel-air mixture, causing combustion. A piston produces pressure forces via fuel combustion that are transmitted to rotate the crankshaft using a connecting rod.

Camshaft

This rotating shaft operates the intake and exhaust valves throughout the engine cycle. The camshaft determines the specific duration and precise timing of the valve opening/closing. So, it ensures timely intake of air, combustion of fuel, and removal of exhaust gases.

Crankshaft

A crankshaft is simply a rotating shaft that changes the reciprocating movement of the piston into rotational motion. The connecting rod transfers the power generated to the crankshaft. The rotational motion of the crankshaft moves the flywheel to move the tractor.

Fuel Injector

A fuel injector injects fuel when the compression stroke ends after atomizing fuel into fine droplets. A fuel injector ensures a good quality fuel-air mixture that offers better engine efficiency and lower emissions.

Flywheel

This mechanical device features a heavy disc that can store rotational energy. It provides consistent power to the crankshaft and keeps the engine running smoothly. Its primary purpose is to prevent speed fluctuations in the transmission system.

How does a Tractor Engine Work?

Most tractors use internal combustion engines, also known as diesel engines. A diesel engine works through the repetition of a cycle of four strokes or stages. The operation cycle of the 4-stroke tractor engine involves the following stages:

Intake Stroke

In the intake stroke, the inlet valve opens while its piston moves down the cylinder. So, the cylinder receives air from outside. As the piston moves to the bottom, the air is filled in the cylinder. At last, the inlet valve is closed.

Compression Stroke

First, the inlet valve is closed at this stage. Both inlet and outlet valves are closed in this stroke. As the piston moves up, the air mixture gets compressed in a tight space, which heats it to high temperatures. When the compression stroke ends, fuel is injected into the cylinder. The ignition occurs spontaneously when the fuel comes in contact with pressurized and high-temperature air.

Power Stroke

Both valves remain closed in the power stroke. Due to ignition, extreme heat is generated inside the cylinder. The piston is pushed down due to the high pressure in the cylinder. This downward movement is known as a power stroke. The generated power is transmitted from the piston to the crankshaft with the help of the connecting rod. The crankshaft begins to rotate and transfers power to the wheels.

Exhaust Stroke

The piston travels upward in this stroke. The exhaust gases move out through the exhaust valves. As the burnt gases are eliminated from the tractor engine, the cylinder can receive fresh air, and the cycle continues.

What are the Different Types of Tractor Engines?

The engine is the most crucial component of a tractor as it provides the power needed to perform different farm tasks. Based on how air is drawn into the engine, the tractor engine can be categorized into two types: Naturally Aspirated and Turbocharged. Go through the next section to find out which engine type is suitable for your farming needs.

Naturally Aspirated Tractor Engine

In a naturally aspirated (NA) engine, cylinders receive air with the help of atmospheric pressure alone. It means there is no external mechanism or forced induction system to force air into the cylinder.

For more power in an NA engine, a larger mix of fuel and air is combusted in the engine. Thus, the manufacturer increases the number of cylinders or their bore to increase the volume of the combustion chamber and derive extra power. This is why naturally aspirated tractor engines are likely to have a larger displacement. The popular tractor models in India that come with a naturally aspirated engine are Swaraj 855 FE, Mahindra Yuvo Tech+ 575, Eicher 557, etc.

Turbocharged Tractor Engine

A turbocharged engine is equipped with a turbocharger for force induction of extra compressed air into the engine. This turbocharger has two main components: a compressor and a turbine wheel. The exhaust gases emitted by the engine enter the inlet port of the turbocharger at high pressure. The turbine wheel spins because of this high-pressure air. This also makes the compressor wheel spin, which causes a vast amount of air to be drawn in and expelled via the exhaust port.

This compressed air travels through an intercooler to be injected into the cylinders. The role of the intercooler is to cool the air, which is heated due to hot exhaust gases. The turbocharged engines are powerful enough to produce the same or even more power output with a smaller capacity than NA engines. Even at lower RPMs, they offer more torque. Thus, the initial acceleration or pickup is excellent. The popular tractor models that come with turbocharged engine are New Holland 3630 TX Plus Special Edition, John Deere 5310 Gear Pro Trem IV, John Deere 5075 Gear Pro 4WD Trem IV, and many others.

Tractor Engines by Fuel TypeTractor Engines by Fuel Type

Tractor engines are also categorized by fuel type they use, which impacts their operating costs, power output, and how well they handle different farming tasks. The following are the main types of tractor engines based on fuel:

Diesel Engines: Diesel is the most common type of fuel used in tractors. It is because they have a higher compression ratio, which results in better fuel efficiency. Additionally, diesel engines produce higher torque, which is a basic requirement for a tractor.

Hybrid Engines: Hybrid tractors combine traditional combustion engines with electric power, resulting in better fuel economy and lower emissions.

CNG Engines: CNG tractor engines are an eco-friendly choice for farmers as they run on natural gas. These engines make less noise than diesel engines and offer good mileage for light to medium farm tasks.

Petrol Engines: A petrol engine is an internal combustion engine that converts chemical energy into mechanical power. They are lighter than diesel engines, which can be advantageous for smaller tractors like Swaraj Code.

Hope you now understand how a tractor engine works. It will help you maintain and service your tractor. Also, you can now see which engine type is most suitable if you are looking to buy a new tractor. Remember that a smooth-running engine is crucial for your tractor as it has a huge impact on its performance and fuel efficiency.