i adjusted my valve lash last night on the 22r and ran into a little hangup... the adjusting screw on ex valve 3 is stuck. i loosened the locknut like all the others that i adjusted but the screw would not move. i was only gonna very slightly tighten that one anyway, so i decided not to force it and maybe make things worse... this is my daily driver work truck, by the way, so i just let it go and finished the procedure.
anyone have any ideas why that screw would be stuck? i'd like to adjust it a little.. should i just try harder to turn it? what if i break it? hard to replace?
thanks.

 

I think if it breaks I'd do a head gasket/timing chain while I was rebuilding the rocker assembly.