Use of turbocharger in diesel engine

Types of turbocharger in diesel engine

The use of turbocharger in diesel engine has become popular in many modern vehicles, especially trucks. A turbocharger, also called a turbo, is a forced induction device used to boost the power and efficiency of an internal combustion engine. It consists of a turbine and a compressor housed in a single unit. The turbine gets its energy from the exhaust flow, while the compressor draws in ambient air and pushes it into the engine. With a turbo, the engine can breathe better, and more power is generated without using extra fuel. Given the benefits of turbocharged diesel engines, many people are curious about how they work. But first, here are the different types of turbochargers in diesel engines.

• Single turbocharger: Single turbochargers are the most commonly used type of turbochargers in diesel engines. They are simple and affordable. This is the type of turbocharger that most people think about when the word ""turbo"" is mentioned. A single turbo contains a single turbine and compressor. The size of the turbo can vary, and each one provides a different level of boost. Smaller single turbos spool up quickly, but they provide limited boost. Larger single turbos provide more boost, but they take longer to spool up.
• Twin-turbochargers: Twin-turbochargers are two turbochargers fitted into a single engine. This setup can be achieved with either two identical turbochargers or two different ones. When two identical turbochargers are used, one is assigned to each bank of cylinders in a V6 or V8 engine. The first turbo handles the low cylinders, while the second one handles the high cylinders. The result is improved power delivery across the entire power band. In engines with an inline configuration, such as an I5 or I6, two different turbochargers are used. A small turbo is placed to work with the lower cylinders, while a larger turbo is paired with the upper cylinders. The small turbo spools up quickly and provides low-end torque. The larger turbo takes care of the mid-range and top-end power. The combination of the two turbochargers results in a flat torque curve.
• Variable geometry turbocharger: Variable geometry turbochargers are designed to optimize airflow through the turbine. This is achieved by adjusting the angle of the turbine blades. By changing the angle of the blades, the VG turbo controls the amount of boost produced at different engine speeds. This helps to eliminate turbo lag and ensures a more linear power delivery. It is worth mentioning that variable geometry turbochargers are more expensive than the other types.
• Electric turbocharger: An electric turbocharger uses a battery-powered electric motor to spin the turbine. The electric motor eliminates turbo lag by ensuring the turbine reaches the desired speed immediately, irrespective of the engine speed. Electric turbos are still in their infancy, and most of them are experimental.

Specification and maintenance of turbochargers in diesel engines

• Regular Oil Changes

  The oil must be changed regularly according to the maintenance schedule. Clean oil keeps the turbocharged engine lubricated and cool. Old oil can cause damage over time.

• Quality Oil Filter

  A good oil filter traps particles to protect the turbo. It is important to use a filter with the recommended specs. The filter should be changed regularly, too, to maintain proper flow.

• Air Filter Maintenance

  The air filter stops dirt from entering the engine. It must be inspected often and replaced when worn out. A clogged air filter can restrict airflow and affect turbo performance.

• Cool Down Time

  After driving hard or towing a load, the vehicle should not be turned off immediately. The turbo needs a few minutes to idle and cool before shutdown. This prevents damage from heat.

• Inspect Hoses and Lines

  The hoses and lines that carry oil and air to and from the turbo should be checked regularly for cracks or leaks. Worn components need replacement to avoid turbo problems. Maintaining these parts is just as important.

• Check Wastegate Operation

  The wastegate regulates boost pressure from the turbo. It should be tested that it opens and closes correctly. A faulty wastegate can cause too much or too little boost, affecting performance.

• Monitor Boost Pressure

  A boost gauge lets the driver see if the turbo is producing the expected boost level. Too high or too low readings may indicate a turbo issue requiring diagnosis.

How to Choose Turbocharger in Diesel Engine

A suitable turbo diesel engine is often chosen based on the needs of the end users. Here are some factors to consider when selecting a suitable turbocharger for a diesel engine.

• Consider the Engine Size and Type

  The engine type and size plays a crucial role in determining the right turbocharger. Larger engines often require more power generating turbochargers, while smaller engines may require less power.

• Determine the Power Goals

  Consider the power goals when selecting a turbocharger for a diesel engine. Higher power output goals will require a higher turbocharger, while modest power goals will require a turbocharger with less power output.

• Consider the Driving Style

  The driving style also affects the choice of turbochargers in diesel engines. For instance, a quick spool turbocharger is ideal for a lively driving style and aggressive throttle responses, while a more balanced turbo is suitable for a more relaxed driving style.

• Determine the Budget

  Budget also plays a crucial role in determining the type of turbocharger to be selected for use in a diesel engine. Turbochargers suitable for high performance are often more expensive and may require additional modifications and installation costs.

Ultimately, choosing a suitable turbocharger for use in a diesel engine depends on various factors such as needs, preferences, budget, and lifestyle. Setting out the priorities and needs helps in making the right choice.

How to DIY and replace turbochargers in diesel engines

Replacing a turbocharger in a diesel engine isn't a task that should be taken lightly. However, it's a project that can be accomplished with the right tools, knowledge, and patience. Here's a step-by-step guide on how to replace a turbocharger in a diesel engine:

• Step 1: Preparation

  Before starting the replacement, ensure that all the necessary tools are at hand. This includes a socket set, wrenches, screwdrivers, and possibly a torque wrench. It's also important to have the new turbocharger ready for installation. Make sure to disconnect the battery before starting any work on the vehicle.

• Step 2: Remove the old turbocharger

  Start by removing the engine cover to access the turbocharger. Depending on the vehicle's make and model, the turbocharger might be located near the exhaust manifold. Use a socket set to loosen and remove the bolts holding the turbocharger in place. Carefully disconnect the exhaust pipes and the intercooler pipes from the turbocharger. Be cautious when handling these parts as they might be hot from engine operation. Once all the connections have been made, the turbocharger can be lifted out of the engine bay.

• Step 3: Install the new turbocharger

  Take the new turbocharger and ensure it's prepared according to the manufacturer's instructions. Carefully place it into the engine bay and reconnect all the pipes and connections. Make sure to tighten all the bolts and screws securely to avoid any leaks or loose parts.

• Step 4: Final checks

  Once the new turbocharger has been installed, reconnect the battery and double-check everything before starting the engine. Ensure there are no loose parts or leaks from the pipes and connections. Start the engine and allow it to run for a few minutes before taking the vehicle out on the road. This will help ensure the new turbocharger is working correctly and there are no issues with the installation.

Q and A

Q1: Why do diesel engines use turbochargers?

A1: The primary aim of turbochargers in diesel engines is to help the engine inhale and exhale better. By doing so, the engine can produce more power without using more fuel. The additional power from the turbo allows for quicker acceleration and makes it possible to drive larger vehicles, such as trucks, with a heavier load.

Q2: Is it okay to idle a diesel engine with a turbo?

A2: Yes, it's perfectly fine to idle a turbocharged diesel engine. However, giving the engine a minute or so before turning off the ignition is essential. This practice allows the engine's oil to circulate adequately, cooling the turbo and preventing any potential damage from heat.

Q3: Can a turbo be added to any diesel engine?

A3: In short, it's possible to add a turbo to any diesel engine. However, the procedure can be intricate and vary in difficulty based on the engine type. It's advisable to consult with a professional mechanic or refer to detailed guides for specific instructions and considerations.

Q4: Does a turbo change the sound of a diesel engine?

A4: Yes, adding a turbo to a diesel engine alters its sound. The turbo introduces a new, distinctive noise that many find appealing. Additionally, other modifications, such as installing an aftermarket exhaust system, can further change and potentially improve the engine's sound.

Q5: Do turbocharged diesel engines require more maintenance?

A5: Turbocharged diesel engines do need some extra care, but it's not a huge hassle. The upkeep tasks are similar to those for regular diesel engines. It's vital to stick to a regular maintenance schedule, like changing the oil and filters on time, to keep the turbo in top shape.