Scotty love your videos. I have a 1973 Chevrolet C20 with a 350, and 3 speed automatic trans. I recently replaced the carb to a edelbrock 650. Runs perfectly at idle but hesitates bad when you start to drive it. I’ve tried carb adjustments nothing seems to work. What could it be?
You are having a problem transitioning from the idle circuit to the secondaries. If your idle mixture screws are turned out more that about two turns, your idle jets are too small. Also check your accelerator pump diaphragm for proper function and the squirter jets it feeds.
Why the down vote? We are trying to help you.
Also check the float levels and needle seat. WHY THE DOWN VOTE?
chill doc. most of the time people hit it accidentally.
That's what they all say.
If the engine has the original distributor, it has a vacuum spark advance and the actuator is attached to the bottom side of the distributor. The vacuum hose may be connected to the wrong vacuum port on the new carburator or the diaphram could be ruptured not letting it advance like it needs to. The correct port on the carb is not supposed to have vacuum present at idle, but will gradually increase vacuum during a decrease in atmosphere pressure as the intake of air increases when the throttle is opening. The vacuum level returns back to almost zero when the engine stops accelerating like at cruising speed. If you don't have documantation for the carburator as to which port connects to the distributor advance, get a vacuum gauge with a hose and see which port increases in vacuum as you open the throttle.
Does it like bog down when you step on the gas? Or is does it have actual throttle hesitation from the pedal to the motor? If it bogs down it would most likely be a carburetor issue, if there's throttle hesitation when you step on the pedal I would check the throttle connection linkage.
