That small hole on the carburetor's venturi or the narrow end of the carburetor tube is called the carburetor jet. It is situated right where vacuum is created to allow fuel to be drawn in by means of the suction made from such vacuum. The jet makes sure the cylinders receive carefully balanced mix of air and fuel, so it has to be of the right size to be able to draw in the right amount of fuel. Besides considering carburetor jet sizes, it is also a must that you do a routine maintenance on your carburetor to make sure the jet won't be plugged up.
Carburetor jet cleaning is the best way to ensure that the jet is free of clog and is always capable of drawing in the correct amount of fuel. Since it is a part of the carburetor, cleaning it means cleaning the entire component. Here are the steps on how to clean the carburetor and its carburetor jet.
What you'll need:
- Shop rags
- Safety goggles
- Lubricant spray
- Small wire brush
- Choke and carburetor cleaner
Step 1: Make the carburetor accessible.
With your car's engine off and completely cooled down, take the air filter housing off. This will make your carburetor more accessible. You also need to locate the throttle control that's connected to the carburetor as this will let you manually run the engine while you are carrying out this DIY maintenance task.
Step 2: Protect nearby components and surfaces.
Get your rags, the lubricant spray, and the carb and choke cleaner. Put some around the carburetor's base and other surfaces nearby. These rags will absorb chemical overspray and will stop any run off. This is necessary as these chemicals can damage the painted surfaces near the carburetor jet.
Step 3: Clean the exterior part of the carb.
Make sure to wear your safety goggles before spraying lubricant into the outside of the carburetor. You can use the carb and choke cleaner if the area is filthy. Heavy sludge and oil buildup can be eliminated using a small wire brush. Brush the dirt off before the spray gets dry.
Also lubricate the connections and other attached moving parts like the throttle area linkage. Allow the fluid to penetrate for a few minutes and wipe it up.
Step 4: Clean the carburetor.
Apply a small amount of carb cleaner directly into your car's carburetor. Rid the engine area of the rags and other tools and start the engine. Do not make the mistake of spraying lubricant into the carb.
With the throttle control, start the engine. It's wise if you run the engine via the throttle control because it allows you to operate the motor at a higher rpm while you are spraying in more carburetor and choke cleaner. A generous amount of cleaner will help push itself all the way to the clogged carburetor jet. This fluid will also help avoid stalling the engine out.
The proper way to apply the cleaner is to spray in short spurts and run the engine faster. After that, slow the engine down to normal idle and re-spray the cleaner again. Repeat these steps for several times.
Step 5: Test the carb and the carburetor jet for proper operations.
Allow the vehicle to run for several minutes at normal idle. Turn the engine off and put the air filter and housing back. Take your car for 10 to 15 minutes drive or until it gets hot. This will allow the carb cleaner to run through the system.
You don't need to notice a dramatic increase in the vehicle's performance after cleaning the carb and the carburetor jet; the important thing is that all the signs of plugged up jets have been eliminated. Among the symptoms that you should no longer notice are engine stalling after the engine has been fired up, inability of the car to accelerate properly, as well as engine hesitation.