Why do I get recurrent blisters (clear, not around mucous membranes) on top of my nose that are on/off for 7+ days, not acne or clustered.?

Viral infection. Most likely this represents a herpes virus infection. You will need to see your primary care doctor to make sure there is nothing else wrong with your immune system. If the lesions occur often then your make need to be placed on antiviral medications daily.