Hey guys! Just to update everyone, the thermostat was indeed bad! it was running way to long past the cut-off point
(too cold) also the frosting on the suction tube was caused by an OVERCHARGE of F-12 from the previous owner. had a local vending guy look at it and he said, that when the T-stat was going bad, someone thought the freon was low and overchared it, (probably didn't have a gauge set and just dumped a 12-oz can of F-12 into the machine till it seemed "cold" enough)
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'> Well a new T-stat and a recovery of the over-charged F-12, She's cooling fine!
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'> thanks for all your help, I'm off to get a COLD one! JohnieG Hope this lesson helps other people.