If ignition is ok:
Check the power piston if you have a Rochester B carburator. If it´s stuck it will not start, too. Had this problem on 2 of my 3 trucks I owned.....


1947 Chevrolet 3800 1-ton long bed
292 cui, GM 14 bolt rear-end, 4 x disc brakes
In Frankfurt, Germany
Pictures in the Forum Gallery