Glass Fuel Level Sights. Making sure your float bowls have the proper amount of gas in them is important when it comes to ensuring a properly running carburetor. Too much fuel in the bowls will push additional gas into the carburetor and too low will cause the car to stumble as they run dry.If you are trying to reduce the float level while the car is running, this can cause fuel to pour out of the side of the carburetor and onto a hot engine.lass Fuel Level Sights. Making sure your float bowls have the proper amount of gas in them is important when it comes to ensuring a properly running carburetor. Too much fuel in the bowls will push additional gas into the carburetor and too low will cause the car to stumble as they run dry.