Chainsaw Repair

I brought one of these home over the holidays and so far the only problem I found was that the fuel filter was totally varnished up, so much so that it had glued itself to the inside of the tank about 3 inches above the bottom of the tank. The inside of the carb is spotless but got a cleaning and new line anyway. I don't think this saw has many hours on it.

The question I have is about the carb boot. When these go bad, is it obvious from the inside looking from the carb end? Mine looks beautiful from the inside but it seems inspection from the outside is near impossible unless you blow the saw into pieces.