I have a 1968 el camino with a 300 HP 350 engine. I'm starting to get this problem with the carb. I have a 4150 Holley 650 double pumper that is about a year and a half old. I live in the desert were it is very hot. While at work, I'll come out to start my el camino about a 10 hour work day and the engine is completely flooded. I have my gas tank vented and the only thing I can think is happening that the gas is expanding in the heat and is pushing the gas in the fuel line pasted the needle and seat and is flooding out the engine very badly. I can get the engine to start after about 2 minutes of cranking the starter. Need to get this problem fixed and was just wondering what I could do. Maybe a new needle and seat for my Holley would fix this problem?

I would change out the needle and seats, or maybe the float level is way too high. I just had a float level problem, it turned out to be stripped threads in the fuel bowl where the needle & seat thread into. This caused the foat level to change all the time. I had to change the fuel bowl. Dave

Thanks Dave,
I've got to get this problem fixed! I know for sure the threads aren't stripped out. It's a new carb. Cranking on the starter for 2 minutes to get the engine started is really starting to be a big problem!

I just had to put two new floats in my new Holley because they had filled with gas.

I would have to agree with dsr in that if you lowered the float level that would more than likely cure your problem.