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How To Clean The Needle Valve On Carburetor

Once the needle valve is not able to stop the flow of gas and filled the float bowl with too much gas, it can flood the carburetor that will make the engine malfunction with a high possibility of damaging it.

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Carburetors installed on your engine uses needle valves in the float to either stop the flow of fuel or add fuel to the float bowl. The needle valve flow control allows the carburetor to maintain the required amount of gas on the float bowl. As soon as gas runs out of the float bowl, the float moves down going to the needle valve. This motion will create an opening that will allow gas to fill the float bowl. Once gas has filled the float bowl to its required amount, the float rises and the needle will cut off the flow of gas. Once the carburetor runs out of gas, and the float bowl did not function as it should, the engine will not function as well. It can either have a hard time starting or it will totally not start at all. On the other hand, once the needle valve is not able to stop the flow of gas and filled the float bowl with too much gas, it can flood the carburetor that will make the engine malfunction with a high possibility of damaging it.


As such, constant cleaning to ensure optimum performance of your float bowl and valve must be performed. You must check if your carburetor, bowl float and needle valves cleaning How To Check Needle Valve On Car Engines.In doing this, you will need a small screw driver (flat-head), hammer, carburetor cleaner, pliers and cotton swabs.


Initially, you need to locate the air cleaner to take out the air intake tube. The air intake tube is a square black plastic tube that can be removed by wiggling it and pulling it off with a hand. Locate the wing screw on top of the air cleaner and have it loosed by turning it counter-clockwise, remove the wing nut by pulling it. Remove the air cleaner cover and set it aside.


Once the cover has been removed, you will find the float bowl. Loosen the screws attached to it by turning it counter-clockwise, remove it completely. Using a screw driver, locate the pin on the carburetor’s body. Dislodge the pin. Once the pin is removed, you may now disconnect the float from the carburetor.


You will find the needle located inside a hole at the front of the float. Use a carburetor cleaner and spray it on the float needle valve. Pull the needle using pliers. Be careful not to bend or damage the needle. If the needle is damaged, the valve will have difficulty closing or opening; as such, the float bowl might have too much or too little gas in it. Place the needle in a small container, spray carburetor cleaner on it and leave it for a while to loosen deposits or harden dirt.


By using a cotton swab sprayed with carburetor cleaner, clean the edges of the port removing any dirt and deposits in it. Replace back the clean needle to the port and tap the pin into the body of the carburetor. Put back the float bowl on top of the float tightening it by the two screws. Place the air cleaner back on the top of the carburetor; cover it with the air cleaner cover. Insert the air intake and tightening it with the wing screw.