Please Help! i'm desperate

[69shorty]

Hi there folks, I recently parked my truck for a few months, I was working out of town for 3 months....I come back and I started it up and it idled beautifully one night, and the next day....I would start it up and it would idle for like a minute maybe less, and it would just die.....I don't know what the problem is, It will only stay on for about 10 seconds sometimes, then it just dies, I tried a different carburetor off of my brother-in-laws truck and it did the same thing, I don't know what the deal was, but I remember when I was driving it before I parked it, sometimes it would bog down when I pressed the gas all the way...anyways Please Help, thanks lots!