How to fix stumbling and hesitation problems.

If your car hesitates or stumbles when you try to give it some throttle, whether it's off idle, or when you're driving down the road, then you most likely have an issue with the accelerator pump.
To learn how to fix this type of issue, you can either watch the video below, or scroll down and read the article I wrote about it.
95% of the time, stumbling and/or hesitation issues stem from this on your carburetor... the accelerator pump.
When you give it the gas, your engine takes-in a gulp of air, but your engine doesn't run on air and needs fuel, so in order for your engine to get that fuel before the main jets can start working, the accelerator pump mechanically squirts-in a bit of fuel to go along with the initial gulp of air so it can accelerate. When this pump goes bad or is out of adjustment, it won't deliver that much needed initial shot of fuel and it will cause your engine to stumble and fall on its face. On a Holley, this is where the accelerator pump and linkage is as seen in this image.

And this is the accelerator pump and linkage on an Edelbrock or Carter AFB type of carb.
This is the squirter on a Holley carb. When you give it throttle, you should see a nice squirt of fuel coming out of this, down into the barrels of the carb. If it is gurgly or nonexistent, then you know your accelerator pump is either broken or out of adjustment.
Mind you, the squirt of fuel coming out of here ONLY happens when you are giving it throttle, as in moving the throttle linkage and it ONLY squirts for literally about 1 second and then stops on its own.

This is what the stream of fuel should look like coming out of the squirters when everything is working right. And as I said earlier, this fuel squirt only lasts about 1 second and then stops on its own.
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