I too have this problem. With my 89 Ram 50 2.0L
First off, feel free to correct any of this info I'm about to spill.
Mostly occurs after driving across town and idling in traffic too long, ie when the engine is hot. I talked to Weber cause I just installed one of their carbs. They tell me it is a flooding issue (not sure i understand the basic flooding concept) caused by a either improper tuning, and miht have to do with a vacuum leak. He said you can test for a vacuum leak by running the engine and turning the mixture screw in all the way. If the engine still runs, there is a vacuum leak. Sorry if that's common knowledge.
Anyway I replaced every cracked line and gasket, and plugged all the ports. It runs better, and I can get the mixture screw in range, but still the engine runs when it's all the way screwed in. It happens less often, but after lots of idling it still stalls. I took it to a shop this week (for the first and last time) hopping they could settle it. They did find and repair a vacuum leak. And that is ALL they found. For $120. They did also re-tune the carb. Of course they tell me she is good to go. Alas, it stalled on my way home from the shop (perhaps related, perhaps another issue entirely) while i was gassing to get up a hill. It did start up right away, but I have not been able to drive it enough to know if the hot start stall is still an issue.
This may have been an issue before the Weber too. I did have stalling problems then but it's definitely gotten worse.