Leaking valve cover gaskets

To the caller Michri (?) with her leaking new valve cover gaskets: did you try retightening? Sometimes a new gasket will compress as it gets hot then cools and settles in and you will find all the screws/nuts to be loose. Happened to me more than once.

This probably doesn’t apply, but I thought I’d share a success story. My 90-ish Dodge Dakota’s V-6 has stamped steel valve covers (with, like, four teeny-weeny bolts holding each) and had a chronic problem with leaks – especially at the back outside corners on each side.
I tried the cork gaskets, the rubber/steel composite gaskets, and then Blue RTV – nothing worked. Finally, I decided to combine all three. I put the cork on the head (to straddle the narrow cast edge of the head), the rubber/steel guys on the top (their thin rubber strip seals nicely against the wide flat surface on the valve cover), and Blue RTV in between – gluing the two pairs of gaskets together.
By applying the RTV between the gaskets and gently screwing the covers in place, I think the goop compensates for any unevenness in the valve cover, while gluing the gaskets together. Once they’re fastened together, the steel part of the composite gaskets reinforces the cork, keeping it aligned with the mating surfaces. After a bit of curing time, I finished torquing the cover bolts, and the thing runs as clean is the day it was sold. Mahvelous!