OK you say you have have
all of them cracked?... and your No#1 you say is squirting a clear flow of fuel ( No air ) now close it
tight then move to the next one do the same... by the time you get N0#3 clear and closed she will fire.
FWIW when Im doing
work like this I keep my sea cock closed till it does fire then immediately open it..you will not harm your impeller doing it this way and no risk of flooding your engine.
If your getting fuel squirting you dont have the fuel shut off engaged..the only thing keeping it from firing
is air..monkey with it long enough it will fire.
Hope this helps
OH PS: If you have a hand prime
pump use it throughout this operation and as well as soon at the engine fires to help
work air out of the system...the engine may want to stumble and want to or even will die a couple times.. just keep pumping and it will help a lot and eventually work itself all out.