Adjusting rockers with new lifters?

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Aug 15, 2001 | 11:37 PM
  #1  
When adjusting rocker arm lash, the normal procedure would be to tighten the rocker lock nut when the cam is not engaging the lifter until you cannot twirl the pushrod by hand, then another 1/2 to 3/4 turn after that.
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But with brand new lifters, the lifter is not pumped up any. What I have discovered is that I can do the procedure above, wait a little while, and the push rod becomes as loose as can be again.
Should I go back and re-adjust them after letting them sit for a while or turning the motor over a few times to pump the lifters up/down???
This is with hydrualic roller lifters.
Thanks



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Rob
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Aug 16, 2001 | 12:01 AM
  #2  
No. Don't go back and re-tighten them or they will be too tight, the bleed down is normal.
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Aug 16, 2001 | 12:05 AM
  #3  
No. After you get zero lash by spinning the pushrod until it stops then adjust the rocker 1/2 turn, you have now set the valve lash. That 1/2 turn is compressing the spring in the lifter. It will push back up after a while. Adjusting it farther puts too much valve lash in the lifter.

1/2 turn lash is all that's required. If you want to use a dial gauge you can set the lifter preload to .030" (the same as 1/2 turn).

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Aug 16, 2001 | 09:56 AM
  #4  
There were a few that I did readjust. So should I go back and remove the rocker on those and let the lifter set for a while and then reinstall again without readjusting over time?
Thanks
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Aug 17, 2001 | 02:28 AM
  #5  
Yes, lossen them up and let them sit awhile. Also don't tighten them until they don't spin and then 1/2 turn, more like a 'slight' drag with no up and down movement+1/2 turn.

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Aug 17, 2001 | 09:05 AM
  #6  
Thanks Joel.Since I have the intake off, somebody was telling to tighten them down just until the plunger on the lifter starts to depress, then just another 1/4 to 1/2 turn. Should about the same as the twirling pushrod method.
Thanks
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Aug 17, 2001 | 02:45 PM
  #7  
THey squeeze down easy when new becuase there's no oil in the adjustment chamber inside the lifter- only air and a light spring. First time you fire the motor and oi pressure comes up you will never be able to squeeze them down that easy again.

Air is compressible, oil is not.
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