223 spitting back thru rebuilt carb

Good evening. I'm new and this is my 1st time posting. I just purchased a stock 55 F100 w/223. Been driving it now for about 5 mo. when all of a sudden I went to start it and it was flooded and had to have towed home. Let it set over night wouldn't start. Removed air cleaner carb was dripping gas down the throat. Found a holley 1904 rebuilt by FORD MOTOR CO. back in 6/57 (still in original box w/ packing slip). Checked the throttle shaft and it is tight. It was shipped to Washington St. and has been there since. Installed it and adjusted. When idling the tach wavers between 500-550. Took it for a spin and when accelerating it spits back through the carb. Don't know what to do next. Any help would be greatly appreciated. Thanks.

Did you check if the float level or wet fuel level is correct? Other things to check is to reset the valve clearance (adjust the rocker arms). Reset or check the points to proper dwell angle, regap the plugs, check base timing. Check or re torque the intake manifold bolts, do a compression test, if you want you could also re torque head bolts if you take the valve cover off. Good luck when everything is right they idle and run great!

bubba, I hear what you're saying but the truck was running like a top before the flooding indecent and I will ck the float level. Don't you think the issue will be with the carb itself since it was running great before. I see you live in Flagstaff Az. I'm in the Phoenix area and also have a place in Munds Park just s/Flagstaff that we use in the summer. Thanks

For sure the carb is the first thing to check out, (float level and other settings) and you would also know the trucks operation better then me without seeing it. That said a bad carb can sometimes fowl out a plug or plugs this could account for your slight RPM change they will sometimes clean themselves with use getting it warmed up good and driving it. Did you try taking apart your old carb (the fuel bowl) to see if it can be repaired with a new needle and seat or a new float, that is usually all they need to fix them? Yes I moved to the Flagstaff area about a 1 1/2 years ago to retire, we stayed once at Munds Park when were moving here it's a great place. Good luck Edited

I suggest getting a carb rebuild kit and taking the carb apart yourself. Clean everything thoroughly and carefully. Blow out all air, fuel and vacuum passages with filtered compressed air. DO NOT USE the fuel inlet fitting, needle and seat that comes in your rebuild kit. If you do, you will always have a flooding problem. Clean and re-use your old ones. These carbs are the simplest in the world and you should be able to rebuild it in very little time.
If you ever need to replace your fuel pump, that could be a problem in the future. The new fuel pumps deliver 5-7 psi fuel pressure. It could be enough to overcome the float in the carb and cause flooding.