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 adjusted).  Now you are ready to adjust cylinder 3, the front of the car – left side valves.

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!).

12) Start your engine – warm it up and then do your oil change (See Oil Change Procedure).

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