I have in my home a Johnson Forced air Furnace second floor installation, now that being said my home was built in 1974. The furnace is in a small room (12X7ft) and this room get hottier than I think it should like a 85 maybe 90 degrees. But now the pilot lite won't stay lite after the furnace runs a while just wondering what it might be Just a possibility of what it might be? I have replaced the thermocoupler with in the last month

You probably have a dirty pilot burner which is normally pretty easy to clean. There are a lot of videos online showing how to do so. Just do a search for "how to clean a gas pilot burner".