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decked heads + hydro lifters, rocker geometry?


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Hey guys

 

 

A bit more than 2k miles on a freshly built high compression ea81. From the get-go I had some valvetrain noise, a bit more than stock. Very solid "sewing machine" with intermittent ticking at idle, from one lifter regardless of oil/engine temp.

 

Much of this chatter I attributed to the hydro valves, and figured it would work itself out. Kicking myself now, I didnt tear them down for cleaning. They all felt good, so I simply hosed them down with fresh oil and installed them into the new motor. 2k miles later the noises are still there. I do believe I have at least one lazy lifter. But the rest of the valvetrain noise Im wondering about.

 

All valve lash has been adjusted, and readjusted, and readjusted. Noise never changes. The heads were decked .015 So Im considering the possibility of improper rocker arm geometry. .015 isnt much, so I didnt think of it during the build. All hardware was reinstalled without measurements. All I did was loosen all the adjusters, and do I baseline hydro lifter valve adjustment. Currently running 1 turn from "zero lash".

 

pretty long-winded I know, but for those with shaved/decked heads, have you noticed additional valve train noise? If so, have you done anything to address it? or just run it?

 

 

 

Thanks. :cool:

 

BTW, the motor runs out great without any odd noises at revs. Valve train noises are only apparent at idle. Slightly noisier at hot idle.

Edited by Idasho
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i did a 87 chaser ea81 hydro motor planed the heads and reset the valves and it made nosie in the valvetrain i just base set the valves to the spec but was still nosiey. I think the bottom of the lifter had been pounded in a bitt i never had them out but have seen them worn thru the bottoms before

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You could try something like a BG engine flush to see if the lifters quiet down. I tend to install copper valvetrain shims under the valve springs on the performance builds and sometimes shave the end of the valve a little. You can pull the lifters in car which you of course know.

 

Which pushrods are you running? I don't like using the adjustable ones with the hydraulic lifters and have seen that be noisy.

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All hardware is stock. Lifters, rockers, and pushrods, valves, all stock.

 

The heads were worked over. A good cleaning, fresh valve grind, a few thread-serts and shaved .015

 

Im thinking my pushrods are a bit too long. You mention shims, where axactly are you installing them? Im thinking at this point I could experiment with a small shim under the rocker assembly, though I do not want to negatively effect total valve lift.

 

If the one lifter doesnt shut up soon, Ill have to drop the pan. Last resort at this point though.

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