|The process of adjusting our valves is not that hard if you understand
what is going on and
why we are doing it this way.
Yes we have hydraulic valves and it's said "hydraulics' need
But, we have 2 valves per intake and exhaust ports. When we
have a noisy valve train, part of the problem
could be that the valves of any one intake or exhaust port
could have one or more valves opening and
closing at different times. The excessive tolerances when
the valves are out of adjustment create some
of this excessive noise.
The ideal set up is to have both valves
of a particular intake or exhaust open and close at the same exact time.
When this situation exist then we will have a much quieter
To obtain this, one of the best ways to set our valves is
to use a dial indicator for an adjustment to
the "Nth" degree or as we say "Zero Tolerance".
|Preparation: We need to apply a dial indicator
to rest upon a rocker arm finger in a stable manner as the slightest deflection
of the mount will give false readings. I use a magnetic base and mount it
to a suitable
place on the frame to hold the dial indicator. The indicator
tip will rest upon a rocker arm valve tip finger
or upon the push rod finger portion of the rocker arm. The
latter is where I usually prefer to position the dial indicator.
For this animated demonstration the dial indicator will appear
upon the nonadjustable rocker arm
finger. Before we start loosening valve tip adjusters we should
first check to see if our valves are out..
Let me inject here again and add that, in this article here
when we put a .005 feeler gauge under a rocker
arm finger the indicator will read .005, in the real world
when we consider the fulcrum and pivot point,
as we have with the rocker arm fingers and rocker arm shaft,
and the laws of physics we know that if the dial indicator isn't the equal
distance from the pivot point as the valve tip, then we might read .004
for example instead of .005 . Not trying to confuse you but when you actually
do it, you will have been
forwarned and hopefully not scratching your head as to why
the readings aren't the exact measurement of the feeler gauge.
|Figure 1: This shows the indicator set to
"Zero" on the indicator dial.
The left most finger is resting upon the valve trip.
The right most finder, (the adjustable rocker arm finger)
is not resting upon it's designated valve tip.
This we don't realize as of yet. (refer
|Figure 2: In figure 2 the rocker arm is opened
enough to slip in a feeler gauge.
Let me point out here that the thickness is not an issue as
the feeler gauge is just a *standard for
the adjustment of the valves.
* Standard: meaning it is a constant value that will not change
from one area to another.
For this application we are going to use a .005
(5 thousandths) feeler gauge.
|Figure 3: In this figure we slip a .005 feeler
gauge under the left most valve finger.
(note the indicator shows .005) (refer
|Figure 4: Here we put the same .005 feeler
underneath the right-hand valve finger.
Notice here that the dial indicator only reads .003 .
This indicates to us that there is a .002 thousandths
difference between the left valve finger and the right finger.
If the readings had been the same
the valve adjustment would have been OK and no adjustments
would be needed.
Since they are off we will proceed. (refer to animation)
|Figure 5: This figure shows the feeler gauge
removed. The dial indicator is upon "Zero" and
we've loosened the lock nut on the right hand adjustable valve
finger and screwed the adjuster
tip down to meet the valve tip. Then re-tighten the
(Take note here that this is where your sense of touch will
be of the utmost benificial use. If you
adjust the tip too far downward then you will begin to lift
the leftmost finger tip upward causing
an out of adjustment condition in the opposite direction.)
When you first feel the adjuster tip make
contact with the valve tip , stop. (refer to animation)
|Figure 6: Here we are opening up the rocker
arm assy again to apply the .005 feeler gauge.
|Figure 7: Here the .005 feeler gauge is applied
under the left most finger, it reads .005
(refer to animation)
|Figure 8: Here we move the .005 feeler gauge
to the right-hand finger tip and again check our
reading. Note here that it also reads .005 on the indicator.
This means that both fingers are equal and will touch both
valve tips at the same time.
(this situation is as shown in figure 5 as well.)
As the push rod applies pressure to the rockerarm assy
the valves will both start to open
at the same time as well as close at the same time.
If the reading are not the same then you need to repeat
step 5 through 8 again till you acquire the
same readings on the dial indicator on both sides. (refer to animation)