If there's no gas in the clys.after You try and turn her over like that ,maybe and this happened to Me and My brother in law,We had pulled his SB out to rebuild it for a race on sunday we got the engine rebuilt and back in the car but it had gotten real late when we tried to start it also backfired thru the carb than all it would do is start and die gas starved ,what had happened was when it backfired it blew part of the intake gasket out installed a new gasket and ran on sunday. Maybe the backfire blew the intake gasket out a little and you're not getting the gas out of the manifold.

Also check the valve adjustment.

Pete

1952 Chevy 3100
In the Stovebolt Gallery
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