Valve lash adjustment.
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Valve lash adjustment.
Ok, this is what I got. 1980 F100, with 300 I6. Step son heard a light ticking noise and decided to tighten all the rocker arms down tight. Now, as I understand, all I have to do to fix it is to loosen all the rocker arms and then bring each cylinder to top dead center and then tighten both the intake and exhaust to the point where i can no longer move the rods up and down, but can still spin them slightly with my fingers. The lifters are already preloaded, so the half turn or full turn to tighten isn't needed, would this be correct? Thanks in advance!
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From: Virginia
Why would the lifters be pre-loaded already?
If you have bolts holding the rocker arms down, there is no adjustment, tighten them down and leave it. If you have nuts, then do your procedure and then turn them 1/2-3/4 turn to preload the lifter.
If you have bolts holding the rocker arms down, there is no adjustment, tighten them down and leave it. If you have nuts, then do your procedure and then turn them 1/2-3/4 turn to preload the lifter.
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Maybe I am misunderstanding what preload means, I thought that preload meant that there is oil already in the lifters, is that not correct? If that is the case, then I would not need to do the 1/2 to full turn. Correct? Right now, if I bring #1 cylinder to TDC, i can only adjust the fre play out of the lifter, it will not allow me to tighten 1/2 or a full turn, most i can do is close to a quarter turn
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Yeah, Chevy's! This 1980 F100 has 90,000 orginal miles on it, couldn't pass it up! Been sitting since 95. So, each cylinder to TDC, then wind down until it stops, right? I've done transmission work, but not engine, and a newbie to Ford engines. Thanks for your input!
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From: St Albert, Alberta
There is a procedure to check to see if everything is in spec. (Repeat for each cylinder at TDC compression) using lifter bleed-down wrench bottom the lifter and check the clearance between the rocker arm and the valve stem tip. Allowable 0.100" - 0.200". Desired 0.125"-0.175" . Use longer or shorter service push rods to achieve proper clearance if out of spec.
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Wow, sounds easy enough! I'll wind them all down at TDC, then torque them to 20. Thank you very much!
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From: Virginia
Maybe I am misunderstanding what preload means, I thought that preload meant that there is oil already in the lifters, is that not correct? If that is the case, then I would not need to do the 1/2 to full turn. Correct? Right now, if I bring #1 cylinder to TDC, i can only adjust the fre play out of the lifter, it will not allow me to tighten 1/2 or a full turn, most i can do is close to a quarter turn
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