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1958 chevy 6cyl 235 hydramatic transmission

two weeks ago after a long storage period i started to revive the truck, i finally managed to get it started and have been returning to the garage every 4-5 days to start it,so far the motor appears to be runnung well and started quickly.

today i had a difficult start, during cranking i noticed gas oozing from the bottom of the carburetor and when it did finally start gas was slowly dripping from somewhere around the linkage area, it ran for a while but eventually stopped.

i disconnected the fuel line from the carb and it started right up, ran for about 2 full minutes with no fuel line hooked up, in addition i noticed smoke coming out of the hose port on the valve cover that goes to the air cleaner. after it stopped running with no fuel line i re connected the line and it ran well with no noticeable gas dripping just like prior times

i am trying to make sense of what happened mechanically
perhaps i pumped the pedal prior to start a few extra times, could this mess up everything so bad?

thanks

Are you using the original gas tank without a good cleanout or replacement? Gas tanks have a bad habit of forming sludge and varnish during long term storage, which can do massive engine damage when it's mixed with fresh gasoline. The most common one is valves sticking in their guides which can get severe enough to make the valves stick, bend pushrods, break rocker arms, and bend valves if they come into contact with the pistons.

NEVER, EVER, POUR FRESH GAS INTO AN OLD TANK!

I use a 2-gallon plastic gas can with a piece of flex line to the fuel pump when doing a resurrection of a barn find vehicle, and either remove the gas tank and get a radiator shop to clean it out, or replace it if a repop tank is available.

Most likely, your carb leak was caused by flooding, the result of a piece of rust or other gunk from the tank getting under the inlet needle valve in the carburetor. It's like a toilet tank fill valve that won't shut off. Removing the fuel line and running the float bowl dry allowed the gas to flush the crud out as it refilled the float bowl. You got off lucky once- - - -better deal with the gas tank now, before it bites you in the behind- - - -they almost always do!
Jerry

These old carbs will sweat condensation when they are cold running. 1st check to make next time is to find out whether it's water vapor or fuel. A simple smell test will tell you.

It could have also been a loose connection of the fuel line that you may have corrected when you R&R'ed it.

3rd swag is that fuel may have leaked out from around the throttle shaft. This is common in worn out carbs. If it isn't sucking air (as in a vacuum leak) it's not too serious yet.

Smoke/vapor from the valve cover is probably piston blowby which is common in high mileage engines. As the rings/cylinders wear and the engine consumes more oil vapors, these increased combustion byproducts that normally escape through the draft tube will make their way up to the head through various passages and out the vents. Sometimes as an engine is ran more the blowby can decrease (as was the case in my 49 216) but it will not completely go away as the engine is worn past the point of no return. Normally if the blowby decreases as the engine runs don't worry too much about it. But a rebuild is in it's future.

These old engines can get alittle cranky to get going when cold. I use the following to get mine going.
1) floor the gas pedal to get a good squirt of fuel in the manifold.
2) fully close the choke.
3) set my home made fast idle setter on the hand throttle knob to get the engine to run at a faster rpm than what the std fast idle circuit provides on a Rochester B carb.
4) turn key on and depress the stomp starter, once it starts immediately open the choke and let it warm for a few minutes at fast idle, then remove the home made fast idler from the hand throttle knob. It will still idle slower than when warmed up but it won't stall. If it acts like it's going to stall I will manually keep the rpm up at idle.

If it doesn't start at 1st using the above, it takes an enormous amount of fuel and cranking to get it going. But thankfully it usually starts right up within a couple secs of cranking, even on the coldest days in which case I pump the gas pedal 2 times

Good luck
Dave