Hotrod Lincoln posted an excellent way to adjust valves.
Using his method you will see every valve/rocker arm moving.
Post back and let us know if it helped solved your problem.
Listed below is a copy & paste of his post.
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Companion cylinders are: 1&6, 2&5, and 3&4.
These pistons reach top dead center at the same time,
one on the compression stroke with both valves closed
(ready to adjust)
and the companion cylinder is at the top of the
exhaust stroke with the exhaust valve closing
and the intake just beginning to open.
This condition. with the valves moving in opposite directions,
is called "rocking".
Let's get ready to adjust the valves on the #1 cylinder- - - - -
Turn the crankshaft clockwise,
and watch the rocker arms and valve springs
on the #6 cylinder.
The last rocker at the firewall (#6 exhaust)
will begin to compress the valve spring, causing the valve to open.
Keep turning. The exhaust valve will open fully and begin to close- - -
the spring will relax. Keep turning.
Just as the exhaust valve reaches the closed position,
the second rocker from the rear (#6 intake) will begin to move.
Stop turning.
Go to #1 cylinder and adjust both valves.
They will both be fully closed, with the piston at top dead center.
Continue turning the crankshaft and watch the valves on
#2 cylinder as they assume the "rocking" position.
This will happen 1/3 of a turn of the crankshaft after #6.
Adjust both valves #5.
Turn again until #4 rocks - -adjust both valves #3.
Rock #1 - -adjust both valves #6.
Rock #5 - -adjust both valves #2.
Rock #3 - -adjust both valves #4.
On a hydraulic lifter engine wait 15 minutes
before starting to allow all the lifters to bleed down
to their normal running position.
A mechanical lifter engine can be adjusted the same way
with no time delay before starting.
