The gasoline overflow drain hole got plugged up.  The rains came and even with the gas cap on tight, water got into the fuel tank.  I checked the fuel pump (A-OK), drained the tank, cleared the line, put in a new gas filter but it still won't start.  Dribbling gas or spraying starting fluid into the carburetor will cause it to fire up for an instant then quit.  Did I miss doing something?  I guess it's rebuild the Rochester carburetor time.

From my no-start thread on this board three years ago:  OK ... so it's two + months later ... and the weather and kids'sports have both abated so I got some weekend time to tear down the carb. (Nothing external succeeded ... priming, starting fluid, etc.)   No big surprise - the needle (valve) was seized solid.  When removed with a bit of Gumout and a bit of gentle force, there was an orange crystalline residue on both the needle and the valve body ...  despite the whole fuel system being treated with stabilizer late in the Fall before layup.  Hmmm .....

I recall a thread here a few years ago where a member showed photos of the contents of a C3 tank which was being siphoned. The difference in color from the water and gas from the tank was pointed out in the photos. The whole tank didn't have to be emptied out.

You can fill the float bowl of a Q-jet by pouring gas down the breather tube in the top center of the carb.  If it runs for 30 seconds or so, you have a fuel delivery problem.  Then disconnect the fuel line at the carb and direct it into a container while you crank the engine.  If it is pumping, the needle valve must be stuck or plugged.  If it is not pumping, leave the line disconnected and pressurize the tank.  If gas comes out, the fuel pump is bad.  If gas does not come out, keep disconnecting further back until gas comes out, and you will have found the blockage.

Good Luck
Larry