Valve Adjustments - The Most Important Procedure
For Your Beetle
It would be impossible to overstate how important regular
valve adjustments are for your beetle. Valve adjustments
must be done every 3000 miles in order to make sure that your
engine works efficiently and so that you do not experience a major
engine failure from a tight valve. While 3000 miles is the
recommended distance you should travel between valve
adjustments, you should do the procedure more often if you are having
problems with the way your vehicle starts or the engine misfires
after it is warmed up.
An engine that is misfiring when it
is warmed up is a sign of a tight valve. An engine that
makes excessive noise when it runs may have a loose valve.
There are many great books out on the
market that can guide you through the valve adjustment
procedure, the best being John Muir's "How to keep your
Volkswagen alive" manual. I highly recommend that
you get this book before starting your valve adjustment.
There are other books on the market as well that detail the
valve adjustment procedure. Back in the 70's I had a small
hard cover Haynes or Chilton air cooled repair manual as well as
John Muir's book.
When I bought my first 66 beetle back in
1975, I had no idea of what kind of maintenance was required on
the engine. I figured that an oil change every 3000 miles
would be sufficient to get me where I needed to go. Had I
known about the valve adjustments, I would most certainly have
learned how to do them. Performing the procedure would have prevented my engine
from blowing on the way to work on a cold December day.
Live and Learn!
To do your valve adjustment the tools you
need are available at your local hardware store.
1) A Feeler Gauge with a .006 blade.
2) A Regular Flat Blad Screwdriver.
3) A 13mm Box Open End Wrench.
4) A 22mm Wrench for turning the engine at the generator.
5) You will also need a set of Valve Cover Gaskets.
I have performed this
procedure many times and it usually takes me about a thirty
minutes to do the valve adjustment and another thirty or so
minutes for the oil change. The hardest part of the valve
adjustment is just the laying on the ground for the
procedure...it can be a little awkward.
This is a brief
introduction to performing the operation:
1) MAKE SURE THE ENGINE IS COMPLETELY COLD -
PUT TRANSMISSION INTO NEUTRAL
2) Remove the distributor cap by pulling off
the retaining clips on the side. Move the distributor cap
out of the way so you can see the rotor.
3) Go underneath the car and remove the
valve covers by inserting a screwdriver or open end of a box end
wrench under the cage wires and gently pull them out of their
groove. Oil may come out of the covers as you remove them
so lay some cardboard underneath to catch the oil. Remove the
old gaskets from the covers and wipe them clean.
4) Rotate your engine clockwise by
using a 22mm box wrench (or a socket wrench) on the generator pulley
nut. Turn the engine until the rotor inside the
distributor lines up with the notch on the edge of the distributor rim
(see picture above of distributor above) and the notch on the
crankshaft pulley lines up with the crack in
the crankcase. This should be TDC (Top Dead Center) which
is the position you will need for adjusting the first set of
valves (Cylinder 1). This is the set of two valves at the front (of car)
located on the right side.
5) Each cylinder has one Intake Valve and one
Exhaust Valve (a set of two valves for each cylinder). The
Intake and Exhaust valves are both adjusted in the same manner:
Push down on the rocker arms on the opposite side of the valve
nuts to take up any slack in the valves. Take the .006
feeler gauge and slip it between the valve and the upper end of
the rocker arm. If the blade passes through with no
resistance it is too loose, if the gauge
will not go in or goes in with a great deal of resistance, it is too
tight. If the gap is correct, move on to adjustment of the
next valve. If the valves do need to be adjusted use
the 10mm wrench to loosen the locking nut on the valve. There is a screwdriver slot in the adjusting bolt
which is located in the middle of the locking nut that was
just loosened. Screwing this bolt in or out tightens or
loosens the valve. When you find the correct gap for the valve, you need to hold your screwdriver
in the slot of the adjusting bolt so that it does not move as
you tighten the locking nut.
Once you are done tightening the locking nut you will want to
double check the gap with your .006 feeler gauge (in the event
that it moved during tightening).
6) Rotate the engine counter-clockwise 180
degrees (there should be a paint mark on the opposite side of
the crankshaft pulley notch) until the paint mark lines up with
the crack in the crankcase. If there is no paint mark,
this is the time to paint one on the pulley 180 degrees from the
notches used for lining up cylinder one. Now you can adjust the
set of valves
for cylinder 2, which is the rear of the car, right side
(directly behind the two valves you adjusted for cylinder 1).
7) Rotate the engine 180 degrees counter-clockwise until the notch
again lines up with the crankcase (as it did when cylinder 1 was
you are ready to adjust cylinder 3, the front of the car - left
8) Rotate the engine 180 degrees counter-clockwise until the paint mark again lines up with the crack in
the crankcase. Adjust the valves on cylinder 4 - its your
last set of valves (rear of the car - left side) just in case
you lost track.
9) Put new gaskets on the valve covers and
reinstall them with the wire clips.
10) Put your distributor cap back on.
11) Remove any wrenches from the engine
compartment (you won't want to leave a wrench on your generator
pulley for sure!).
11) Start your engine - warm it up and then
do your oil change (See Oil Change Procedure).