Fast Trak S/D SPUTTERS, LOSES POWER, DIES

Hi all.

My fairly new Fast Trak S/D (50 hrs), has started this habit of sputtering, losing power, dying, sometimes backfiring after about an hour of mowing.

Acts like its running out of gas(which I have done several times). I can sometimes keep it going by setting the choke. it eventually dies.

After letting it rest for a few minutes I start it up and we're good to go for about another 15 -20 min. And then let it rest and restart.

This goes on until its so frequent that its just not worth it. The next day is the same. good for an hour or so and it starts all over again.

Clues: the fuel in the filter varies from 1/4 to 3/4 full. happens on either full tank. gas is fresh.

Is it possible that there is a vapor lock? if so how do I fix that? could it be the fuel pump getting week. could it be something getting heat sensitive?

Its very irritating. I spent a lot of money on this machine with the idea that it wouldn't give me any trouble for a while.

Thanks in advance for your help and your suggestions.