My brick (170,000 miles) has developed a slow oil leak, and while I was staring at the throttle body trying to figure out the way to remove it to get to the breather box, I gazed upon the distributor as well, since that was also suggested as a source of the oil leaks.
What I noticed is what looks like clear silicone sealant applied to the gap between the valve cover and the distributor. See attached image...
(yes, that is oil on the valve cover that is coming from the filler cap, needs a new gasket as well.)

Something doesn't look right, but I am still pretty new to this, so I am asking for anyone with more experience to enlighten me. Should there be some sort of gasket here? There is about 1/8th inch of gap here, is that normal?

thanks!

There are three seals within the distributer that can leak. Perhaps a previous owner or shop tried to fix a leak with silicone on the outside.