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Discussion Starter #1
Happy early President's Day everyone! So I was wondering how often do the valves need to be adjusted? It is once every ??? miles or every couple of years or just when it's needed?

I think my valves are ticking under load and have not adjusted the valves since I got my Mustang in fall of 2013 and probably 20K miles ago.

I've been searching Youtube and can someone let me know if adjusting the valves while the engine is running is correct like video below and if so, how much splatter should I expect?

Appreciate any inputs!
 

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Adjusting with the engine running is messy and pointless. And with the later step-type studs, difficult to accomplish.



If you do not have stepped studs, do this:
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Adjust hydraulic valves with the engine cold.

Do this, and it will run smoothly, and likely with more power:

Disconnect the coil + wire.

Attach a bump switch to the solenoid, or just use a screwdriver.

Turn the engine so the #1 intake valve is fully opened. Loosen the exhaust valve until you can move the #1 exhaust valve pushrod up and down (NOT spinning).
Tighten this valve until no up and down movement can be felt, then tighten an additional 3/4 turn.


Note: Spinning the pushrod can cause a false adjustment, as a slowly collapsing lifter can allow the pushrod to spin freely, thus throwing off the base line of your adjustment.

Turn the engine so the #1 exhaust valve is fully opened. Loosen the intake valve until you can move the #1 intake valve pushrod up and down (again, NOT spinning).
Tighten this valve until no up and down movement can be felt, then tighten an additional 3/4 turn.

Repeat for the other 7 cylinders.

I did this on a friend’s engine that had been adjusted when built, then driven for several years. It was running OK, but not great, you could hear some valve noise. After doing the above, it did not seem to be much better immediately after adjustment, mostly because the lifters had been varnished into position by years of driving. Coupla miles around the block, though, and it was a whole 'nother engine.


Adjusting mechanical valves.

I drove a 289HP daily for 20 years, and every 6000 miles I adjusted the valves, which took less than an hour.

Adjusted properly, they aren't noisy, either, just a high-pitched singing sound.

Factory spec for the 289HP C3OZ-6250-C cam is .022" cold, .018" hot.

The procedure in the Manual is a bit complicated, and involves marking the balancer at 90° points, and then you follow some weird pattern, like I1, E4, I6, E2, or some complex crap. Takes an hour just to figure out what they want you to do.

Do this instead-

Run the engine until it is a full operating temperature. Disconnect the coil + wire.

Attach a bump switch to the solenoid, or just use a screwdriver.

Bump the starter until the second valve on the #1 cylinder is all the way open. This means the one closest to the radiator is closed, on the base circle of the cam lobe. Adjust the valve to .018".

Bump the starter until that valve is fully open, and adjust the second valve.

Continue to adjust the valves in pairs until the RH head is adjusted, and install the valve cover.

Repeat the process on the LH side of the engine. I like to start and run the engine to be sure it is still fully warmed up.

Remove the LH valve cover, and adjust the LH valves to .018".

Very quick, and very accurate.

If the engine has just been assembled, do the procedure cold, at .022”. Then warm up the engine and do it hot.
 

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69 302 rocker studs are of the "bottle neck" style and you simple torque the rockers down, the hydraulic lifters require no adjustment.
 

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69 302 rocker studs are of the "bottle neck" style and you simple torque the rockers down, the hydraulic lifters require no adjustment.
I have seen many a hydraulic lifter that required adjustment. If his studs are the step type, I would personally convert them to adjustable.
 

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I have seen many a hydraulic lifter that required adjustment. If his studs are the step type, I would personally convert them to adjustable.
Not in a factory stock 69 302. Aftermarket cam - sure. He's not asking about converting to screw in studs and guideplates.
 

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Discussion Starter #6
Thank you for the detailed instructions 22GT!

Thank you too Hemikiller!


I believe the engine is bone stock and not sure when it was last adjusted or rebuilt. How do I know if I have hydraulic or solid lifters?
 

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Let’s back up a bit.

My valves are ticking under load?

Define “under load.”
Like, at wide open throttle?
When climbing a hill?

If you have excessive valve lash, they will tick all the time. Not just under load.
Sure it might be more noticeable when cold, or at higher rpm but rocker arms aren’t sensitive to throttle position.

Maybe what you are hearing is knocking, or pinging, or improper ignition timing.
 

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Discussion Starter #9
Let’s back up a bit.

My valves are ticking under load?

Define “under load.”
Like, at wide open throttle?
When climbing a hill?
Actually, I think under load could be wrong. I can definitely hear it when I am at WOT but I can hear it softly when I'm driving and the engine is up to temp. I also hear it when I'm stopped next to another car or next to a wall because I can hear it bouncing off the car or the wall but I don't really hear it when I'm in the garage with the engine running.
 

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Actually, I think under load could be wrong. I can definitely hear it when I am at WOT but I can hear it softly when I'm driving and the engine is up to temp. I also hear it when I'm stopped next to another car or next to a wall because I can hear it bouncing off the car or the wall but I don't really hear it when I'm in the garage with the engine running.
If you can hear it under load, but not when the engine is at idle in the garage, then it's most likely an exhaust leak at the manifold. The lifters in my 302 tick a bit, but only after the engine is fully warmed up and has been driven a bit.

Block the wheels and have someone you trust put the car in gear and while holding the brake, give it a little throttle. Give a listen around the engine. If you have a manifold leak, you'll hear it plain as day. It could be the manifold to head seal, or the manifold to pipe.

Many people make the mistake of using gaskets between the manifold and the head. That's the quick and dirty way and it eventually fails. If you have the time, you'll need to flatten the sealing surface with a large file or sanding board. Youtube video below demonstrates the idea. I have a 16" body board that I use for this. Keep going until you have a solid shiny ring around each exhaust port.

 

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Discussion Starter #13
Thank you for all the tips! I'll check for exhaust leak between the block and header.
 
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