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Well I spent a bunch of time today researching how to adjust my valves because of excessive ticking coming from the valve covers. It doesn't seem that hard, it's just I haven't done it before.

I thought I had it figured out but then I saw a couple of posts that said the 69 302 was different than the 68. Unfortunately, my car is a 68 and the engine is a 69. I don't have a shop manual for 69 and Tom Monroe's book doesn't really cover the difference that much.

I pulled the valve covers and found three of the rocker arms are exceptionally loose. Do I just tighten them up to eliminate the lash when fully closed or is there some other way to correctly adjust the valves?

Thanks ::
 

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The first thing is to determine the types of rocker arms you have. If there is a shoulder on the rocker arm stud, just under the threads, you have positive stop rockers and the adjustment is made with different sized push rods.

Most likely your '69 302 is just like all the other late '66-'69 289's and 302's with fully adjustable hydraulic lifters (there will be no shoulder, and if you removed a push rod, the rocker arm would drop all the way down to the head).

For fully adjustables with the stock stamped steel rockers, I like to adjust them with the engine running. I have an old stock valve cover with the center section cut out, just for this purpose. With the engine running, you simply loosen each rocker fulcrum nut until the valve starts to "clack". Then tighten it JUST until the "clack" stops, then tighten 1/2-3/4 turn past that (I usually just do 1/2 turn).

Don't just tighten rockers willy-nilly. With the engine off, every rocker on a closed valve will have play in it.

BTW, I have 3 '69's, all with 302's and they all have fully adjustable hydraulic lifters. Two of the engines are original to the cars and have '69 date codes.
 

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Make sure that the looseness isn't being caused by worn push rods, lifters or rocker arms. You know if something is a tad shorter from years of wear, it is no longer adjusted properly. My 351 W used to make a tick , driver side rear end of the valve cover. Other culprits could be a rocker arm stud that is backing out. Even if the engine was rebuilt recently,some rebuilders use low quality studs. So if the stud starts to back out of the head...the ticking starts...Its usually the lifter that makes the noise....
 

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If you do have adjustable valves, here is how I do it:

1. Remove the valve covers, and pick a cylinder you are going to set the preload on.

2. Hand rotate the engine in its normal direction of rotation and watch the exhaust valve on that particular cylinder. When the exhaust valve begins to open, stop and adjust that cylinder's intake rocker arm.

3. Back off the intake rocker arm adjuster and remove any tension from the pushrod. Wait a minute or two for that hydraulic lifter to return to a neutral position. The spring inside the lifter will move the pushrod seat up against the retaining lock if you give it time to do so.

4. Now spin the intake pushrod with your fingers while tightening down the rocker arm. When you feel a slight resistance to the turning of the pushrod, you are at "Zero Lash". Turn the adjusting nut down one half to one full turn from that point. Lock the adjuster into position. The intake is now adjusted properly.

5. Continue to hand turn the engine, watching that same intake. It will go to full open and then begin to close. When it is almost closed, stop and adjust the exhaust rocker arm on that particular cylinder. Loosen the exhaust rocker arm and follow the same procedure described before in steps 3 and 4 to adjust this rocker arm.

6. Both valves on this cylinder are now adjusted, and you can move on to your next cylinder and follow the same procedure again.

Time consuming, but the results are solid. ;)
 
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