Carburetor Cleaner

For an older car with a carburetor, cleaning is essential to have the car running properly all the time, especially with a classic car or restoration. The carburetor provides the fuel and air mixture that makes the car run smoothly and efficiently. Your vehicle should be cleaned with a carburetor cleaner from time to time to ensure that it is working at peak performance. The process of cleaning a carburetor with a parts cleaner is fairly simple. It takes roughly fifteen minutes or so, and is fairly easy to do, especially for someone who knows anything about a car.

The first task is to go to an auto parts store and pick up a good carburetor parts cleaner. Some of the more popular brands are CRC or B-12 Chemtool, if just picking up a can from your local store. These are some of the best automotive fluid manufacturers in the business. The brand of cleaner chosen should not matter too much, as most carburetor parts cleaner brands are made from similar chemicals including:

• Acetone
• Xylene
• Toluene
• Methyl Ethyl Ketone (MEK)
• Ethyl Benzene and/or Propane

Remember that safety comes first. One of the reasons these cleaners are so effective is because they are toxic and strong. Do not inhale or ingest these chemicals.

Carburetor Cross Section Diagram

The chemicals in carburetor cleaner do two things. The most important function is to clean the dirt, grime, and residue from old gas from the carburetor. Chemicals like acetone do this, which is essentially paint cleaner. It is a heavy duty cleaner that breaks down and removes the offending residue. The second function is to add a pure fuel mixture using some of the ethyl ingredients. This provides a smooth start and gets the engine running smoothly for a few seconds while the car replaces the gas and air mixture. Using a variety of these chemicals from a good carb cleaner will ensure that the carburetor is running at its best performance.

Carburetor Cleaner Procedure

1. With the engine off, remove the air filter housing. This allows the carburetor to be more accessible and exposes the parts that need cleaning. Get some rags and the proper carburetor cleaner that you’ve decided to use. Find the throttle control, which is attached to the carburetor. It allows the user to manually operate and run the engine faster while cleaning. Place some rags around the base of the carburetor. Some of the chemicals may do some damage to painted areas nearby, and the rags will stop any runoff from creating this scenario.
2. 

   Porsche 6-cylinder Carburetor Cutaway

   Put on safety goggles to protect damage to the eyes, and begin to spray the exterior of the carb with the cleaner. Make sure to spray all the moving parts and connectors, such as the throttle and linkages. Let the fluid set a moment or two as to penetrate all the grime, dirt, old gas, and fuel residue. Wipe it up with a rag to remove the excess cleaner and prevent runoff.

3. Before engaging the engine, spray a minuscule amount of carburetor cleaner directly into the carburetor. This is to begin a proper fuel and air mixture so the car starts smoothly. If using lubricant, do not spray any directly into the carb. Remove any rags and tools from under the hood and start the car. Engage the engine and use the throttle control, as it is important to run the engine at a higher RPM while spraying in more cleaner. This will help the cleaner move through and keep the engine from stalling. Use short sprays of cleaner, push the throttle harder to increase the RPMs, and then slow to a normal idle, decreasing the throttle pressure until eventually it is no longer being manually used. Spray more cleaner into the carb. Repeat this process a few times, using more cleaner and repeating more times based on how dirty the carburetor was.
4. Now run the car for a little while at a normal idle. After a few minutes of idling, turn off the engine, replace the air filter with a brand new one, and reinstall the housing. Now drive the car around local roads for ten or fifteen minutes or until the engine warms up, allowing the cleaner to completely run through the system. Even if there is no performance increase at the moment, it is important to note that it takes a little time, and that this is the proper cleaning process for the carb. This does not mean it did not work. It means it is working. In some cases, if carbon buildup was the problem, however, increased power and fuel efficiency can be noticed almost immediately or shortly thereafter.

For a cleaner carburetor, another option is an ultrasonic cleaner. Many mechanics and car care professionals recommend using an ultrasonic carburetor cleaner for the effectiveness and the safety. Due to the fact that these types of cleaners use less chemicals and rely on ultrasonic technology to remove residue and contaminants from the metal surfaces, they are safer to use for the reduction in necessary chemicals. Ultrasonic cleaners use sound waves at a high frequency in order to agitate the parts in a mild solution and remove contaminants and grime in a safe, effective method. However, these options can be costly and may not necessarily be worth it to most car owners when a can of carburetor cleaner costs less than five dollars.