What zero lash on the lifter rod should feel like?

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Hugomartin

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Should I be able to still barely spin the rod with my fingers then 1/2 to3/4 turn?
 

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Use one finger and slide the side of it perpindicular to the push rod, and when the rod won't rotate anymore you're at zero lash. Using two fingers you can still rotate it at zero lash.
 

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Should I be able to still barely spin the rod with my fingers then 1/2 to3/4 turn?
No spin. It will be able to freely spin and then when it hits zero lash you will feel it get very tight. Then I do 1/2 turn. I use the EOIC method. It makes it super easy, especially if you have a starter trigger switch to bump it over.

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75gmck25

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I have also seen suggestions that jiggling the rod up and down is easier to feel the zero point. When you go up and down it’s a simple go/no go choice (does it move). When you spin the rod you need to calibrate the “feel” of your fingertips to know how hard it is to rotate. YMMV.
 

Hugomartin

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I tried adjusting the rocker arms but still no start
i can only seem to charge my battery to 12.1v . After a couple times trying to crank it drops to 11.6v.
 

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Sounds like the battery is in need of replacement
 

Bextreme04

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I tried adjusting the rocker arms but still no start
i can only seem to charge my battery to 12.1v . After a couple times trying to crank it drops to 11.6v.
Where are you measuring that at? At the battery, you should have ~12.7v for 100% charge. 12.1v is less than 50% charge. 11.6v is basically dead. Do you have it on a battery charger and it won't go above that? Are you just reading it at the dash?
 

Hugomartin

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Where are you measuring that at? At the battery, you should have ~12.7v for 100% charge. 12.1v is less than 50% charge. 11.6v is basically dead. Do you have it on a battery charger and it won't go above that? Are you just reading it at the dash?
Yes I was measuring it at the battery. Thanks for the info I didn’t know 12.1 was only 50%, below is my jump starter I used to charge my battery. It’s definitely a step down from a real battery conditioner charger
 

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squaredeal91

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I've only adjusted chevy rockers while running. But reading this has been interesting, I think I'll try this method next time soon.
 

squaredeal91

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You can probably have your battery charged for free at the local parts house.
 

Hugomartin

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Update , I tried using jumper cables from a donor vehicle and I measured voltage and got 12.7 v with a multimeter on the square body battery but still crank and no start I hear some spark popping noises and it turns over fine just no start... I guess we can rule out a bad battery

I played with the lash settings tightening the pushrods/lifters as I was turning the engine by hand making sure of no play then going a 1/4 turn.

I think I’ll re check my compression on dead cylinders 4,6,8
 
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squaredeal91

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Sounds like you are now trying to diagnose a no start? How's spark, is it orange or blue ? Is there fuel squirting?
 

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Was it running? What if anything did you mess with? If your lash is too tight, you will have starting issues.
 

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Not sure what method you used, but this is the method in the book. Except I don't turn 1 turn, I go 1/2 turn. You can turn 1 turn, but I have had issues with 1 turn before, since then it has been 1/2 turn

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DoubleDingo

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Was it running? What if anything did you mess with? If your lash is too tight, you will have starting issues.
YUP. As I mentioned in my previous post, when I went 1 turn and had issues, it started and ran but the vacuum gauge was bouncing all over the place, so I had to redo them all at 1/2 turn and the vacuum gauge was then steady at 17Hg
 

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