Lawn tractor has been sitting up for 1.5 years. I replaced the battery. Engine turns over strong, but no gas seems to flow into carb. I checked fuel line, fuel is flowing. If I poured a little fuel directly into carb, it cranked but stopped once fuel was gone which I poured in. HELP!

The little bit of fuel has likely turned to varnish and the fuel valve in the carb is stuck closed.

Other possibilities are the fuel cut solenoid if it has one.

This is a typical problem when an engine sits with gas in it. Maybe not in the tank, but the fuel bowl itself.

Some see some help by using Seafoam. You may have to take apart and rebuild the carb.

Diagrams are available on Home - Briggs & Stratton (http://www.briggsandstratton.com), but repair manuals cost $.

Prevention is to start adding Stabil fuel stabilizer at the end of the season, so that the last gas used has the additive. It also makes sense to drain as much of the gas as possible and run the engine until all the gas is used up.