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valve lash adjustment help please

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Old Oct 19, 2014 | 12:18 PM
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83ttopgt
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Got a 289 in a 67 coupe. Fresh rebuild on motor. Had no compression as the rockers were adjusted way to tight by the engine builder.

I backed them off, got it running, tightened them up slowly until they stopped clacking.

Then I went back one by one, to back them off a bit, wait 10 seconds or so, then re-tighten them slowly til the noise stopped, then tried for 1/4 to 1/2 turn extra. Motor falls on its face and dies, wont restart unless I back the rocker off some.

So I redid the whole sequence, but this time slowly tightened after the noise stopped until it started to die, then backed off just a bit until it smoothed out.

Is that an ok way to set the rockers, or might something else be wrong?
Old Oct 19, 2014 | 02:21 PM
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Need to set it based on the type of rockers. Noise doesn't tell you ****.

Are they pedestal or stud?
Old Oct 19, 2014 | 02:24 PM
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They are stud mounted I believe. I will go get a pic right now.
Old Oct 19, 2014 | 02:31 PM
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Here is the rockers, with the cut valve cover I have to adjust them
Old Oct 19, 2014 | 02:33 PM
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I can get it to run pretty smooth, but then when you shut it off and restart, its like it over pumps the lifters or something, cause I sometimes end up with a skip/vibration.

I have no idea whats in this motor, neither does the shop that built it. My dad passed away a few months ago, and it was his car.

I am considering just pulling the motor and building another one. The builder skimped on things like the waterpump. He put the old one that feels like the bearing are shot, back on. there are other things I have found too that make me question the build

What are the odds its a solid lifter motor, I know its an earlier 5 bolt bellhousing pattern.

Last edited by 83ttopgt; Oct 19, 2014 at 02:37 PM.
Old Oct 19, 2014 | 05:07 PM
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How can the shop that built it, not know what's in it? Do they not keep records? That's pretty irresponsible.

Find out if it's solid or hydraulic first, if you suspect there might be a solid cam.
Old Oct 19, 2014 | 06:06 PM
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Originally Posted by 67mustang302
How can the shop that built it, not know what's in it? Do they not keep records? That's pretty irresponsible.

Find out if it's solid or hydraulic first, if you suspect there might be a solid cam.
Probably the same reason the old waterpump, pushrods and a bunch of other crap were re used

I am assuming I will be pulling the intake to determine whats in there
Old Oct 20, 2014 | 06:06 AM
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Pulled the intake. solid lifters.

I know to set them around .022, but now I am unsure about the rest of the valvetrain
Old Oct 20, 2014 | 07:32 AM
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hello;

you also need to see if it has screw in rocker studs and should also check the cam lift and spring pressure. if it has press in studs, they may pull out. if the springs are stock, the valves might float at higher rpms.

if it has under around 510 lift, i would set the lash to .018.

also, if it has high spring pressure or high lift, i would get chromoly push rods.

also, unless those adjusting nuts are pretty tight on the threads, they might back off but you can add a thin jam nut on the top to prevent that or buy polylocks.
.

Last edited by barnett468; Oct 20, 2014 at 07:39 AM.
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