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Valve Adjustment

After changing the oil adjusting the valves is probably the next most important thing you can do to insure a long life for your engine. What you are doing when you adjust the valves is setting the amount of space between the end of the valve stem and the rocker arm that pushes the valve open. This little bit of gap insures that the valve is setting firmly against the valve seat when closed. The valve can tighten up due to either stretching of the valve stem and/or the beating of the valve seat into the valve face. If the valve fails to close completely the exhaust gases escape under great force during combustion and the valve seat and the valve face are burned off, thus a burned valve. It is recommended that the valves be adjusted about every other oil change. They should be adjusted to 6 thousands with the engine cold.

The valve are adjusted from under the car. Unless your are very slight of build it is much easier to raise the car and put it securely on stands.
Next remove the valve covers by prying down the bails.
I always start with #1 which is at the right rear of the motor (actually toward the front of the car) looking at it from the rear. The numbers are on the tinwork in front of each spark plug. The piston on the cyl. that you are working on must be at top dead center on the compression stroke. This is when both valves would be completely closed. The timing mark on the bottom pulley would be lined up with the top of the motor and the distributor rotor will be pointing to the #1 plug wire location on the cap. Normally about 4:00 o'clock position. To be sure you can rock the motor back and forth while looking at the two rockers at the right rear. They should be still while one of the front two is moving. The valves on the outside are the exhaust for #1 and #2. The two in the middle are the intakes. Once you are sure you are on #1 You are ready to adjust these two valves.
Try to slip a .006 feeler gauge between the rocker and the end of the valve stem. If it is loose or tight you loosen the 14mm lock nut on the adjuster screw and turn the screw in or out as needed. Turn only a little at a time. When the gauge will slide through with just a slight drag you can move on to the other valve.
This is a good time to check the rocker for side play. There is a wafer washer next to the rocker on the shaft that holds a little tension on it. If it is broken the rocker can slip back and forth sideways and will make a lot of racket. If it is broken you will need to remove the rocker shaft and replace the washer. It is pretty simple. Just remove the clip on the end and it all slides off. Just remember to put everything back where it came off. Anytime you remove the rocker shaft from one side of the motor those valves will need to be readjusted. If you are real ambitious while you have the rocker shaft off you might want to retorque the lower nuts that hold the head on. Now let's move on to #2 cylinder.
To do this you just rotate the motor 1/2 turn counter clockwise. You may be able to do this by hand. If not you can put a wrench on one of the pulley nuts. You might want to put a mark at the 180 degree point to help you find it easier. You can now rock the motor again to be sure that the next two valves are still while one of the two in the rear is moving to double check yourself. Now you just do the same as you did on #1.
When you are happy with this cyl. turn the motor over another ½ turn counter clockwise and move to the other side of the motor to #3 cyl. This is at the rear of the motor like #1 on the other side. Adjust these and turn the motor another ½ turn counter clockwise and do #4 valves.
Renew the gaskets in the valve covers, reinstall and check for leaks. Simple as that! You can see this done in detail in our Vol.1 General Maintenance video available from Bug Me Video.

Rick Higgins and Crew
Bug Me Video, Inc

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