I can’t seem to find my shop manual so I’m asking here:
What is the correct procedure to adjust the valve lash on a 68 302 and what is the correct feeler gauge?
Thanks in advance.
With a new cam and lifters this is easy, and you need to be sure to never fill a hydraulic lifter with oil when they are new to allow for proper valve adjustment and to achieve proper cam / lifter break in.With the cylinder at top dead center on the compression stroke the lifter plunger should be depressed .050" to .100".
You can use a dial indicator to achieve a precise .070" if you want to be really good. There should be no further adjustment necessary.
On used engines each cylinder is again adjusted at top dead center on the compression stroke. Adjust each valve until the pushrod cannot be spun between two fingers. Then tighten the rocker one half additional turn. Then with a cutaway valve cover in place and with a set of rocker arm oil hole clips installed you start the engine. Each lifter is backed off until it can be heard, then tightened until the clicking goes away. Then one half additional turn to achieve proper plunger depth on the lifters. Repeat until each valve has been adjusted.
Feeler guages only work for mechanical camshafts and lifters.
Good info, cheers.