I have double checked the valves and they are right on spec.
Two things, no... make that three:
1. No they all don't do that. In fact mine never does.
2. End play adjustment is : a) not often needed, and b) should not make the noise anyway.
3. Are you absolutely certain, beyond a shadow of a doubt, that you did not mix up the intake and exhaust feeler gauges?
#3 happens. Exhaust is the front side- right up there where the big ole brown pipe is. Check it again. While you are in there do like New2rt said- check the end play again split the difference. Be certain you are at TDC. When you actually did the end play how did you tighten the nut? Did you actually do a torque wrench THEN a Torque angle finishing step?
If you are certain that you did this entire procedure absolutely correctly... meaning You know with certainty you were at top dead center on the side you were working on, and that the rocker arm was loose on both sides, and that you used the exhaust gauge on the front side top and bottom and that the other side was done with the other gauge on both top and bottom, and you then rotated the engine to do the other side... and that you did follow the rocker arm tightening sequence perfectly then you have what we call a mystery.
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