I just changed my valve cover gaskets and as soon as I start the truck oil starts leaking bad out of the very back corner of the driver side valve cover gasket. The gasket looks to be in place and not hanging out, how do I fix this?

 

Might help if we knew what you're working on.

 

Never changed my f150

but another vehicle i had specifically called for sealant on gasket corners near firewall...was pretty hard to get in position and tighten too. Was isuzu 3.5L. so i did....