I bet a like amount of acetone would net the same results as seafoam. The top end cleaning action could be done with even cold water.....you are adding a cold liquid to hot carbon in an effort to break it up.
After cleaning/rebuilding a lot of carburetors the #1 culprit I find is something that made it past the filter or dried up gas that rehydrates with a deposit. 99% of the time draining the bowl and a quick shot of carb cleaner or acetone will blast out enough particles to get back on the road.
If a fuel additive in the amount of 8oz per 128 gallons was enough to show remarkable engine improvement, the epa would have mandated it long ago as all of the ingredients are available at the refinery.
