Valve lash
Teching In
Joined: Jul 2004
Posts: 40
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If it is not a solid cam then pick a cylinder and make sure that it is at the compression stroke and is at top dead center. Choose the intake valve and move the pushrod up and down while turning the nut on the rocker arm until the slack is gone. Once the slack is gone, give it a 1/4 turn more and it will give you the proper pre load on the lifter. Do the same to the exhaust valve and to the other cylinders and you should be fine. Just make sure that the cylinder you are on is on the compression stroke at top dead center. If it is a solid cam, adjust it the same way above except don't give it a 1/4 turn. You would put a feeler gauge of the lash spec. in between the rocker arm tip and the tip of the valve and slide it in and out and keep turning the nut until you feel it grabe the gage. After all is set, let the engine warm up and turn the engine off and set the lash again to all of the cylinders while the engine is warm. Hope this helps.
1. Valves can be set on a hot or cold engine. A cold engine is a lot more comfortable to work on. Major camshaft manufacturers recommend setting valves cold, to avoid erroneous adjustments on lifters that may be "pumped up" If you are setting valves on a fresh engine that has not been run, everything should be well lubricated before you begin.
2. Remove both valve covers and remove the spark plugs to make the engine easier to turn over(REMOVING THE SPARK PLUGS IS OPTIONAL!). Also, If you are setting valves on all cylinders, it is generally easier and less confusing to just loosen all of the rocker arm adjustment nuts before you begin. This also allows for all of the internal lifter plungers to return to their "home" position.
3. Using a long handled ratchet or breaker bar attached to the crank bolt, turn the engine over in the clockwise direction.
A. Starting with #1 cylinder, turn the engine over until the exhaust pushrod just begins to move up.
B. At this point, stop and adjust the intake valve on the same cylinder.
1) Tighten the rocker until you can roll the pushrod between your thumb and forefinger with the slightest bit of resistance.
2) At this point tighten between an additional quarter to half of a turn.
C. You have now adjusted the #1 intake valve. You will now want to turn the engine over while watching the same intake pushrod that you just set, it will go full open and then begin to close. When it is almost closed, stop and adjust the exhaust rocker arm on that particular cylinder. By following this procedure, you are assured that both of the lifters are at the base circle of the cam and that there is no additional pre-load applied to them from cam lift at this point.
D. You are now able to repeat this procedure on the remaining cylinders.
4.Re-install your valve covers and your valve adjustment procedure is finished
2. Remove both valve covers and remove the spark plugs to make the engine easier to turn over(REMOVING THE SPARK PLUGS IS OPTIONAL!). Also, If you are setting valves on all cylinders, it is generally easier and less confusing to just loosen all of the rocker arm adjustment nuts before you begin. This also allows for all of the internal lifter plungers to return to their "home" position.
3. Using a long handled ratchet or breaker bar attached to the crank bolt, turn the engine over in the clockwise direction.
A. Starting with #1 cylinder, turn the engine over until the exhaust pushrod just begins to move up.
B. At this point, stop and adjust the intake valve on the same cylinder.
1) Tighten the rocker until you can roll the pushrod between your thumb and forefinger with the slightest bit of resistance.
2) At this point tighten between an additional quarter to half of a turn.
C. You have now adjusted the #1 intake valve. You will now want to turn the engine over while watching the same intake pushrod that you just set, it will go full open and then begin to close. When it is almost closed, stop and adjust the exhaust rocker arm on that particular cylinder. By following this procedure, you are assured that both of the lifters are at the base circle of the cam and that there is no additional pre-load applied to them from cam lift at this point.
D. You are now able to repeat this procedure on the remaining cylinders.
4.Re-install your valve covers and your valve adjustment procedure is finished
