Chevy 350 motor problems

[68gmsee]

Couple of things that I would do since you say it did run, timing is correct, you get spark and carb is shooting fuel into the engine.

Get a one gallon container with fresh gas and buy about a 2½ to 3 foot piece of fuel hose.

Remove the hose going into the fuel pump, attach the new hose and place in the gallon container of fresh gas under the truck. It may be that you're fuel is somehow contaminated.

Other possibility is flooding. Too much fuel being introduced into the engine. Usually detected by a strong fuel smell or dark gray to black smoke coming out of the exhaust when it does try to start. If that's the case, open the choke fully, hold the gas pedal down and crank the engine without pumping the gas pedal.