In this article, you’ll learn What is an Air Cleaner. The diagram, Working, Parts, and Types of Air Cleaners in the Engine, is explained.
What is an Air Cleaner?
The engine requires a large quantity of air for the combustion of fuel. In a petrol engine, one part of fuel needs about sixteen parts of air by weight for proper combustion. Because such a large amount of air enters the engine, it must be clean and free from dust or dirt.
The outside air usually contains dust particles, sand, moisture, and other impurities. If this dirty air enters the engine directly, it can damage many important engine parts.
Dust particles can wear the piston rings, cylinder walls, bearings, valves, and other moving components. It can also choke the carburetor and foul the spark plug.
To prevent this problem, an air cleaner is fitted at the air intake of the carburetor or intake manifold. All the air entering the engine first passes through the air cleaner. It removes dirt and dust before sending clean air into the engine.
The air cleaner also reduces the noise created during air intake. In addition, it works as a flame arrester when backfiring takes place in the carburetor.
Types of Air Cleaners in the Engine
Air cleaners are classified based on principles of filtration and the nature of filtering material. The type of filter adopted for a particular engine depends on the atmosphere in which the engine has to operate.
The air cleaners generally used are of the following types:
- Oil bath-type air cleaner
- Dry-type air cleaner
- Oil-wetted type air cleaner
- Paper pleated type air cleaner
- Centrifugal-type air cleaner
#1. Oil Bath Type Air Cleaner.
It is a heavy-duty air cleaner. It is designed in a variety of shapes. The type shown in the figure is designed to be placed on the top of the carburetor and to be clamped to the air horn. It consists of a filter element saturated with oil.
At the bottom, there is a separate oil pan. The operation of air cleaning is carried out in two stages.
In the first stage, the airstrikes on the oil surface and then reverse upward into the filter element. The dust particles are applied to the soil surface and absorbed by it.
In the second stage, the partly cleaned air passes through the filter element, in which the remaining dust particles are retained. Finally, the cleaned air passes to the carburettor through the passage.
Depending on the severity of the operation, this type of air cleaner is cleaned periodically. The filter is removed and cleaned carefully with petrol. The oil in the cleaner is also replaced.
#2. Dry Type Air Cleaner.
It is a light-duty air cleaner. It consists of a cleaning element only and not an oil bath. The cleaning element is a specially pleated element, over which is put a fire mesh screen to provide strength.
This cleaning element is enclosed in a silencing chamber. The figure shows the part of a dry-type air cleaner.
#3. Oil Wetted Type Air Cleaner.
It consists of a filtering element, generally wire mesh, coated with an oil film. The air passes through this element, and the dust particles of the air adhere to the oil film.
This type of air cleaner should be cleaned periodically, about every 800 km, by washing the wire mesh in petrol or paraffin. After drying it properly, coat it with engine oil, allow it to drain, and again fit it for working.
#4. Paper Pleated Type Air Cleaner.
It consists of a filtering element of the resin-impregnated paper. This type of air cleaner is made in the form.
It has a high filtering efficiency. By pleating the paper element, a large filtering surface is provided, and yet the restriction of airflow is a minimum. The element should be cleaned periodically, about every 20,000 km.
#5. Centrifugal Type Air Cleaner.
The figure shows a centrifugal-type air cleaner. In this type of air cleaner, a whirling motion is given to the air, due to which heavy dust particles are thrown out by the centrifugal force to the periphery of the casing, where they leave through slots.
The main airflow passes through vanes set at an angle to correct the airflow to a straight direction and then enters the main air cleaner.
The air is not perfectly cleaned by this cleaner, and hence it acts as a first-stage cleaner on installations dealing with heavy dust concentrations. It is known as a centrifugal cleaner.
Directions for Cleaning an Air Filter:
Check your Owner’s Manual before cleaning the air filter. Always follow the manufacturer’s complete instructions for cleaning and maintenance. Make sure the engine is cool to the touch before cleaning.
- Remove the filter. Take the air filter out, taking care to make sure no dirt or debris falls into the airbox or intake. If there’s any housing on the filter, remove the housing and the wing nut attaching the filter to remove the outer element.
- Apply the cleaning solution. Spray the filter with Simple Green All-Purpose Cleaner and let it soak.
- Rinse. Using a faucet or garden hose, rinse the filter from both sides, starting from the interior towards the exterior to prevent pushing dirt further into the fibers of the filter. Avoid wringing or stretching the filter – they can tear easily. Rinse until the water runs clear. Repeat the process if necessary.
- Dry. Shake the filter to get rid of any excess water, then set it down to air dry. Make sure the filter is completely dry before oiling (if you have an oiled filter) and replacing it.
- Oil and replace. If you have an oiled filter, use fresh filter oil to saturate the entire filter, including the sealing flange and lip. Modern vehicles that use a Mass Air Flow (MAF) sensor require special care when re-oiling these types of filters, to avoid over-oiling and affecting the sensitive wires of the MAF. This could cause it to incorrectly measure air consumption, resulting in a “check engine” light. Apply the oil spray evenly along the crown of each pleat on the filter. Then, squeeze out the excess and return the filter to its housing.