is there supposed to be any gap between the cam and the rocker arm when it is not sitting on the "lobe"? I can move the arm up and down a little. I'm guessing I should tighten the adjustment screw, but I wanted to be sure its not supposed to be gapped for heat expansion or something.
thank you !

Matt.

 

When the rocker arm is on the base circle of the cam lobe it should have some movement, .008 on the intake valve and .012 on the exhaust valve, to be exact, thats the stock cam specs, with the engine hot,

 

google or get a toyota haynes manual that explains how to set valve lash. You will need a feeler gauge which you can get from advance auto, a 12mm wrench, ratcheting works best, and a flat head screwdriver... set intake to 7 and exhaust to 11... works the best for me, and no valvetrain noise at all. if you adjust it without using a feeler gauge, your truck WILL NOT RUN!!! if it does, It will run very bad ! this is a simple task that will screw you over if not done right.

also 7 and 11 is when your doing it cold. I never have done it hot but if it is hot go with 8 and 12