I was wondering when someone would mention silicone... That's what I'd recommend....hey, it'd even help you float
its messy and nasty stuff,,besides that the bottom of the dist cap uses a o-ring,,so if the o-ring is there and in good shape you should not need silicone..
dawgtoy,,there should be a rubber plug in that hole,,the dist cap is vented through the cap,,so with the cap vented to high ground it should be good..Guess you need a rubber for your hole