Regulate the carburetor and replace its gasket.
Some sort of gasket may be blown. Either the Head or the Carb gasket IMO.
edelbrock has a square flange gasket fo it
Nitro glicerine
Yes it will just be sure you use the wright carb. base gasket.
No, but it surfaces every once in a while to get air.
There are several reasons there can be a leak. However, you will want to take the carburetor apart for any leak - purchase the carburetor kit and carefully take it apart. Use the rebuild kit to replace gaskets, etc. and when you put it back together, the leak will also be fixed. Do not use gasket sealer on the carburetor.
Remove the air cleaner and air box. Disconnect hoses and mark them so you know the proper reconnections. Remove the nuts and bolts holding the carburetor to the manifold. Remove the old gasket with a scraper and clean any remaining residue with degreaser. Clean the degreaser off completely. Apply gasket sealant to both sides of the new gasket and apply in place of the old one. Repeat the process in reverse order to place the new carburetor. You'll never see a carburetor installed from the factory with sealant. It's not necessary, and can cause problems if any of the sealant gets into the intake tract.
the engine is out of time or the valves are not adjusted right An engine backfires through the carburetor because it's lean. Check all vacuum connections as well as the gasket mating surfaces. Be sure you have the correct parts. Consult any instructional materials available for this particular carburetor.
Under the hood, on top of the intake manifold.
under the gas tank
Under the carburetor.