adjusting valves - lifters pumped up or not?

rockin_rick

Member
Oct 9, 2003
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With stud mount rockers, does it make ***ANY*** difference if you adjust the valves with the lifters pumped up or not as long as zero lash is accurately found with each method?

Rick
 
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Rick

I tried to collapse a lifter with my finger once and it was harder than I thought it would be to move the plunger.

With that being said, when you are trying to find zero lash, I know that is not the same or an apples to apples compare kinda thing but I don't think pumping them up is a must do kind of deal based upon that.

I've never seen any hyd lifter that was partially collapsed after it had been sitting around.

If you built some oil pressure and pumped them up some, I guess that would be an extra bit of insurance.

I guess by now you can see .....
I'm not sure, lol ...... but I think I can find zero lash based upon the fact that I've not pumped them up and they are not too nosiy.

Later
Grady
 
To me, pumping up the lifters applies if new, or they been out and sat around...You could undo the coil and crank til you have oil pressure and it would help...
I have adjusted them before without being primed, they were new, it just made more racket til they filled up and then things were quiet...
So i say if your just doing the swap and the car was recently run just do em up...
Maybe helpful, maybe not... :D
 
What I mean by 'pumped up' is when you are doing your 1/2 turn (or however many - not at issue here), when it's pumped up, there is a lot of resistance to the turning of the nut (compressing valve spring), and when it's not pumped up, there is little resistance to the turning of the wrench (compressing the lifter). Usually when I readjust my valves, the first few/several will have lots of resistance (pumped up), and then as I go, the others not yet done will bleed down and when I get to them they will have little resistance. I wondered if this would cause a difference in the preload set on the lifters.

In both instances, I assume that the pushrod seat in the lifter is fully up against the stop (clip) when finding zero lash and not compressed. If this is true, does this mean that both pumped up and not pumped up will adjust the same?

Thanks,
Rick
 
I see what your asking...Can't answer that one... I have read of some doing one bank, then re-priming the motor before doing the other bank...I did use that method the last time I set mine...maybe it would help in what your feeling during adjusting ??
 
rockin_rick said:
What I mean by 'pumped up' is when you are doing your 1/2 turn (or however many - not at issue here), when it's pumped up, there is a lot of resistance to the turning of the nut (compressing valve spring), and when it's not pumped up, there is little resistance to the turning of the wrench (compressing the lifter). Usually when I readjust my valves, the first few/several will have lots of resistance (pumped up), and then as I go, the others not yet done will bleed down and when I get to them they will have little resistance. I wondered if this would cause a difference in the preload set on the lifters.

In both instances, I assume that the pushrod seat in the lifter is fully up against the stop (clip) when finding zero lash and not compressed. If this is true, does this mean that both pumped up and not pumped up will adjust the same?

Thanks,
Rick

I understood what you were asking but I did not do a very good job of getting my thoughts on the little puter screen, :bang: lol.

I guess I was trying to say that even if the lifter is not pumped up, you still can find the point of zero lash and full of oil or not, that point is the same.

As you pointed out, the lifters that are pumped up will make the turning of the adjusting nut somewhat harder.

Hope I made better sense this time. :D

Later
Grady
 
Last time I did them, I ran the drill every 1/2 bank, and adjusted them all pumped up. I am considering changing the preload, so am trying to figure out if I am going to do it this way again.

When I did them pumped up, I could find zero lash, then gave them some preload, then backed it off, and it seemed that the zero lash point had changed a bit (maybe 1/16 turn). I didn't really take the time to figure out if it was a consistant amount or if it effected all valves, or my imagination. Has anyone experienced this?

Rick