If its just sticking dont waste time and money on a valve job unless you need one to begin with. This is fairly normal if there old gas in the lines or tank. I broke 4 rocker arms and bent a few pushrods on my 248 after everything was warmed up when I first got her running.

Spray a bunch of wd40 down onto the valve guides and use a sledge to tap the valves. Eventually this will dissolve whatever varnish is left on the guides.

You need to investigate a little more to. If you do a complete valve job and still have old gas in the lines, theyll just stick again and really tick you off.

Jeff

My 1953 Chevrolet
1947.1 Gallery
1972 C-10 1/2 Ton & 1972 C-30 1 Ton