I have a 1975 jeep cj5 304 that's starts good, idles good but after about 30-45 minutes of driving I notice when coming to a stop it wouldn't idle have to feather the gas pedal. Then it would die with out any warning no sputtering no nothing just dies even with rpms up it just shuts off as if you turn the key off. I've looked inside of carb to make sure it's getting gas as it does so I don't think it's a fuel problem.i haven't checked to see if it's a spark problem. But it has done this twice when I try to start it it just cranks and then it seem like it it would start as I was turning the key back to run position i could rev it up butthen it would suddenly die as if I turn key off. Then I could let it sit for 20 or 30 mins and it would start up and run fine. Any ideas?