Valve cover install on a 348 engine

[Impala Steve]

I noticed a leak on the rear part of the driver side head so I am replacing both valve cover gaskets. I bought a pair of Best gasket brand valve cover gaskets. I tried to line them up on the valve cover but noticed they had some tabs on them and cut them off. What are the purpose of the tabs on those gaskets? Also what type of adhesive should be used on the valve cover to make the gasket stick to the surface? Do I need to use thread locker for the valve cover screws?

 

[Murphdog]

The "tabs" that I think you are referring to fit snugly into notches in the perimeter lip of an OE tin valve cover. These help to locate and hold the gasket into place. I normally use weatherstrip adhesive to "glue" the gasket to the cover. You could put a THIN film of silicone on the head side if you thought necessary. Silicone on the cover side will just "grease" the gasket and it will want to squeeze out of place if your not real careful, unless you let it cure before install. Aftermarket valve covers may or may not have notches to accommodate the gasket tabs. I would not use thread locker on the screws. Make sure your crankcase ventilation system is functioning properly or you may still have a leak when your done!
Jeff

 

[BSL409]

1958 348 Valve covers did not have the notch cut outs yet started in 59

 

[Impala Steve]

Valve cover install is done. Cut off the tabs since my valve cover gaskets and used Permatex #2 gasket sealant on valve cover then gasket and buttoned it down. No leaks so far.