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Discussion Starter · #1 ·
I kinda feel like an idiot asking this, but this is my first ford, and this seems really wrong.

I have a stock 289 in a 68 mustang, stock cam, stock hydraulic lifters, and a set of flotek heads with valve guides (bad combination I know but I'm using whatever is laying around to try and get this running for my grandpa before winter)

I measured and ordered the correct length pushrods, but when I go to lash the valves I run into a problem. I set lash like normal, but the rockers wiggle side to side and hit the poly locks, I can tighten them further so that they don't hit, but then the pushrods no longer rotate and preload seems way to high.

here's a link to a video to show the movement

do they need to be tighter? am i doing something hugely wrong? This problems seems to come from running the stock cam, which is putting the rockers rather low?

Thanks for any help, apologizes if this is a stupid question.
 

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How did you measure for the "correct" length pushrods? Have you checked
the contact pattern to ensure that your length is correct?
Punchline- if your pushhrod lengths are correct, you will be able to set the
valves correctly. (provided you have no jacked up / collapsed lifters)

And yes, the stock '68 C code 289 cam has pretty much no valve lift whatsoever.....
 

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I don't see any pushrod guide plates in your video. What's keeping the rocker arms centered on the valve stems?
 

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Discussion Starter · #4 ·
I used an adjustable pushrod tool to measure them, changing it until the rockers contacted the center of the valves. They seemed weirdly short to me, you have to use the tip of a wrench to tighten the poly locks, but i figured it was just because of the short stock cam.

there are guide plates, and the pushrods are the correct size for them. pushrods don't move side to side at all, only the rockers
 

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As long as your guide plates are keeping the pushrods in line your rocker arms should remain in line as well.
 

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I used an adjustable pushrod tool to measure them, changing it until the rockers contacted the center of the valves. They seemed weirdly short to me, you have to use the tip of a wrench to tighten the poly locks, but i figured it was just because of the short stock cam.

there are guide plates, and the pushrods are the correct size for them. pushrods don't move side to side at all, only the rockers
It's not just where it contacts it initially, but how it travels across it. Did you do something like this:

 

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Not sure if its the reason but those Rockers look like the Comp Cams Magnum Steel Roller Tip ones and from the times I have seen folks use them they don't have a poly lock like that. They just have a nut. Here is a picture of them:

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You know which brand of Rocker you are using? And I also didn't see the guide plates in the video.
 

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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.
 

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Discussion Starter · #11 ·
Thanks for help everyone! As I'm sure you all expected, it turned out to be a dumb mistake.

Ordered the correct length pushrods, but got shipped ones that where significantly to short. Didn't initially occur to me to check them when they showed up, but that turned out to be the problem. Being as I still have to wait for the right set to get here, I got rid of these weird Chinese rockers and went full roller, and will just measure for pushrods again.

To answer questions, I think the rockers are these: Small Block Ford Steel Roller Tip Rockers
I really don't recommend them, and yes, I promise the heads have guide plates.
 

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Interesting. That's the first thing I check is that I got what I requested. Glad its "fixed" though.
And from where did these pushrods come?
 
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