Tractors

I bought a Poulan PRO PB175A46, in February of this year; upon delivery of my "new" lawn tractor I discovered that it was built in 2014. The store that I purchased it from says that warranty is as new warranty. In second month of ownership I have already replaced the deck belt and both blades to my dismay; now I am in the 8th month of ownership and I am beginning to have fuel delivery problems; at first I thought maybe a bad filter so I replaced the fuel filter last week, today it had a re-occurance of the same problem...like it was starving for fuel, after only using for less than an hour. Does anyone know whether these machines are prone to "vapor lock" problems. I never had this problem with any other lawn tractor that I have owned, however, it is the first that I have owned that had a Briggs and Stratton engine, all my mowers in the past had Kohler power. Can someone give me suggestion what to do? I live in Central Florida and it is always rather hot here.