gas out the exhaust?

Me again, 1980-81 kaw 750ltd 4cyl

got the carbs to stop leaking,bought a second hand rack of keihns

now it seems like #1 cyl. isnt firing, boosted it with a battery pack last night and she ran shitty fer abit and leaked/sprayed gas outa the muffler.

now i got a clear inline filter should it be full of gas?cause its only half full.

Anyways i got a vac petcock and dont know if its the problem,i rebuilt it but dont know if i did it right.

What would cause it to start ,spit gas out the mufflers,and die then no start at all? the #1 exhaust pipe is cold,Is it the Petcock,coil or carbs? I got new plugs too!

this is pissin me bad, if ya can help me ,please i would be gratefull

Steve

sounds like the #1 carb is flooding into the engine. what does the plug look like?

Plug is dry, how do i measure the volts at the coil to see if thats it?
thank you for the reply
Steve

well, the wire will be green or black (i think). check the voltage there.