If you ever change your heads, camshaft, or you're just upgrading your valve train,  you will need to readjust
the rocker arm / valve / push rod setup.  Unfortunately, this is not a simple bolt down and go item.  Take your
time, watch what you're doing, and you shouldn't have any click clacking when you're done.  The following
procedure is for adjusting stud mounted roller rockers with hydraulic lifters.  You will need to have the valve
covers removed and a method of rotating
the crank clockwise by hand.  During the
procedure, work on one intake/exhaust
set (cylinder) at a time.  In this example,
we'll use the number 1 cylinder located at
the front of the engine on the passenger
side.  The very first roller rocker is sitting
on the intake valve and the second roller
rocker is resting on the exhaust valve.  
How can you tell?  Look at the exhaust
header and the location of the header tube
in relation to the valve location.  They will
                              typically line up with
                              each other on the 5L
                              Ford engine).

                              The idea is to set the
                              pre-load and tighten
                              the roller rocker while
                              the lifter is resting on the camshafts base circle or heel.  This ensures that both the
                              intake and exhaust valves are closed while you're trying to set the pre-load.

  • To start, rotate the engine in it's normal clockwise rotation by hand
and watch the intake and exhaust valves on the number one cylinder.
As the exhaust valve just begins to open, stop rotating the engine
and focus on the intake roller rocker on that same cylinder.  If the
push rod was snug against the lifter, loosen the intake roller rocker
and allow the lifter to return to its normal position.
  • To get the proper pre-load, begin tightening the intake roller rocker
while moving the push rod up and down with your fingers.  Ensure
that the push rod is seated properly in the lifter and roller rocker cup.
Once the up and down play is gone, start feeling for a slight
resistance while turning the push rod with your fingers.  It won't be
much beyond that point.  I like to move the push rod up and down at
first because oil on the parts will hide a bit of the turning resistance.
This point in slight resistance is called "Zero Lash".
  • Your intake roller rocker is now ready to be tightened at its final
setting.  For a street driven vehicle, tighten the adjusting nut 1/2 - 3/4 of one full turn further than
your zero lash point and lock the adjuster into position.  For a race application, it's suggested to run the
setting slightly loose at 1/8 - 1/4 turn past zero lash.
  • Now that your intake valve is adjusted properly, it's time to adjust the exhaust valve on that cylinder.
  • Rotate the engine clockwise again and watch the intake roller rocker that you just adjusted.  The intake
valve will open and then close.  When the intake valve is just shy of being closed, adjust the exhaust
valve for cylinder number 1.  Use the same procedure listed above to obtain the proper zero lash, and
tighten the roller rocker adjusting nut according to your application.
  • The intake and exhaust valves are now properly adjusted for cylinder number 1.  Follow the same
procedure on each of the remaining intake/exhaust sets (cylinders).
  • Although this should be done as one of the first steps, make sure your push rods are the proper
length.  Consider taking a mirror and/or feeler gauge, and check under the roller rocker arm to ensure
proper clearance between the roller rocker and the top of the valve spring retainer.

On a side note:  

  • If you are installing new lifters, it's not necessary to soak the lifters in oil prior to the install as long as
you prime the engine with oil prior to start up (according to Crane Cams).  However, I usually dip / coat
them in oil on the install.
  • There is a hole on the side of the lifter.  It doesn't make a difference which direction it faces.
Valve Adjustment For Stud Mounted Rocker Arms
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