Are you sure the exhaust isn't plugged?
You could disconnect the line at the fuel filter, if you don't have the tool to remove the line at the engine, and run the fuel pump. You don't have to get the full qt., after it runs a few seconds, you'll know if it would have pumped a qt. if you'd have waited. To run the pump, pull the relay and connect a jumper across pins 85 & 86 and the pump will run. I like to check right on the line at the engine.