setting valve lash with new lifters jeep 4.0

as said, no adjuster on the jeep 4.0. you can rotate (to base circle) so your not compressing the spring as you torque to 19ftlb. or you can just tighten them down evenly. both ways are fine, however you cannot tighten one all the way without running the one on the same bridge with it or your bent that bridge and the rocker wont ride correctly on the valve stem top.

your lifters need to be preloaded .020 to .060 max. Hence the pushrod checking tool.

This is where I am getting confused. you mention torqueing to 19ftlbs, which is what a bunch of videos and other online research says to do....but the instructions sent have no mention of this so I am lost. I set zero lash, then I used that calculation to add another half turn. this is suppose to put my right at .025 preload which was in the recommended adjustment. But this is far from 19ftlb. I tested it and I beleive it took another 3/4 to 1 and 1/2 turns to get it to 19ftlbs.

This is what is throwing me off. is this what you mean by both ways are fine? I can do either or?
 
ftthe only logically thing that I can think why there are two different ways that I have been able to find is that

A) you measure using a pushrod checking tool at exactly zero lash then add the needed preload height on top of that. This gives you the exact height of pushrod to torque it down to 19ftlbs without compressing the spring

option b) Using the pushrods that came with the kit since nothing has been taking off the block nor the head, set zero lash then add an extra half turn to set to proper preload. Since the nut is I assume a locking nut no need to worry about it backing out.

Am I correct in assuming this or am I completely off?
 
A) you measure using a pushrod checking tool at exactly zero lash then add the needed preload height on top of that. This gives you the exact height of pushrod to torque it down to 19ftlbs without compressing the spring

this.

make sure you on the lowest point of your cam lobe (base circle)

you will probably be fine with stock push rods. But I still recommend measuring to be sure.

Here is a linky that may give you some in site to this and another way to measure your lifter preload.


lifter preload - Jeep Strokers

Also make sure you run a break in oil or some of this additive. https://www.napaonline.com/en/p/LUR...6cKiS_IvO-Hq1FT27mW9IS8w92ApaikhoC05IQAvD_BwE

Also be sure to run 5w30 cold weather and 10w30 warm. It needs to be able to reach everything quickly on start up. thicker oil will take longer to reach your bearings and will smoke cam bearings quickly. your engine needs 10 psi for every 1k rpm (approx.) to lubricate properly.
 
throw that in the trash.
why do you say that? The reason I ask is because this was the way I was shown how to do it back when I worked on SBC motors and the guy who taught me owned his own shop for 40+ years so I am curios. Is there a particular reason why that is bad or doesn't work or is it more based of opinion like ford vs chevy guys type thing?
 
why do you say that? The reason I ask is because this was the way I was shown how to do it back when I worked on SBC motors and the guy who taught me owned his own shop for 40+ years so I am curios. Is there a particular reason why that is bad or doesn't work or is it more based of opinion like ford vs chevy guys type thing?


It doesn't apply to your engine as I understood it with my limited cognitive ability.
 
It doesn't apply to your engine as I understood it with my limited cognitive ability.


….Really?????? "limited cognitive ability." I am going to hope and assume that you are just joking. No one is questioning your cognitive ability. THERE IS A DIFFERENCE BETWEEN ASKING A QUESTION, AND QUESTIONING ONES INTELIGENCE. I ask questions to learn not to get people pissy which apparently happens on here.

No one is saying you are wrong....well I am not saying you are wrong. My issue is I am looking for an EXPLANATION as to why it doesn't apply to my engine or why it cant me done the way I was taught and the way both comp cam and howards cams both have instructions to do. I assume places like comp and howards have put a lot of money into research and development and have a reason they are saying to do it that way (not saying they are right). I also assume you have experience one way or another in this subject, at least I would hope so since you continue to reply to all my posts before. I am once again just trying to understand what is wrong with they way I have been taught and that the companies are saying to do?

I just did there instructions to see if it can be physically done and did not run into any issues. So it is not impossible to do.....the questions is what am I missing if this would not work? It helps to understand instead of just being told what to do like a 4 year old child. The more I learn and understand the better. Not to sound like an A## hole but there have been a lot of my questions on previous posts and this one were I am told what to do but never really explained why something will or will not work (earlier cam questions posts). That does not help me.

So if you or anyone else has insight as to why or why not I would greatly appreciate it, so I can finally finish this Sh$t box I love. I will say it one more time just to make sure I am clear. I just want to understand why it wont work or what problems it may cause so I understand for this project and future projects.
 
….Really?????? "limited cognitive ability." I am going to hope and assume that you are just joking. No one is questioning your cognitive ability. THERE IS A DIFFERENCE BETWEEN ASKING A QUESTION, AND QUESTIONING ONES INTELIGENCE. I ask questions to learn not to get people pissy which apparently happens on here.

No one is saying you are wrong....well I am not saying you are wrong. My issue is I am looking for an EXPLANATION as to why it doesn't apply to my engine or why it cant me done the way I was taught and the way both comp cam and howards cams both have instructions to do. I assume places like comp and howards have put a lot of money into research and development and have a reason they are saying to do it that way (not saying they are right). I also assume you have experience one way or another in this subject, at least I would hope so since you continue to reply to all my posts before. I am once again just trying to understand what is wrong with they way I have been taught and that the companies are saying to do?

I just did there instructions to see if it can be physically done and did not run into any issues. So it is not impossible to do.....the questions is what am I missing if this would not work? It helps to understand instead of just being told what to do like a 4 year old child. The more I learn and understand the better. Not to sound like an A## hole but there have been a lot of my questions on previous posts and this one were I am told what to do but never really explained why something will or will not work (earlier cam questions posts). That does not help me.

So if you or anyone else has insight as to why or why not I would greatly appreciate it, so I can finally finish this Sh$t box I love. I will say it one more time just to make sure I am clear. I just want to understand why it wont work or what problems it may cause so I understand for this project and future projects.


I have tried to help you. I am finished.
 

My turn.
Assuming you have the OEM style rockers, you simply torque the center bolt to spec, which i have always determined to be 24 ft/lbs. Base circle, up, down, sideways, slant 6, whatever. On a 4.0 with the OEM style rockers, that is all you do. Period.
I have built countless, seriously I cannot begin to tell you how many, 4.0 Jeep engines and every single one, from my first one in 1997 until my most recent 4.7 stroker sitting in my shop right now, I have set the last that way.
Now if you have roller rockers, you do have to take additional steps.
 
I am not saying that the way you guys have said you have done it is wrong...…….I am trying to figure out why the way I was shown and the way the Instructions clearly state to do it is wrong? Can anyone answer that? I'm not trying to be mean or rude. If someone is going to say I cant do it that way or it doesn't work I am wanting to know why it won't. If that is to much for someone to explain then maybe it is best they stop "helping" me. I really don't think me asking why something doesn't or won't work is such a terrible thing.

I have been sitting in my garage with this motor setting preload both ways multiple times the past few days to see why in fact the way the instructions say to do it won't work. I have turned the motor over several times......nothing is binding, catching, or anything, and everything appears to be working without any issues. I am nor have I ever said that the way I am suggesting is right. Nor have I said the way others have said to do it is wrong.

I am asking why would the way the instructions are saying to do it is trash and should be thrown away?
 
The way they are doing it is essentially the same way we are saying to do it. In this case since they use standard hydraulic lifters, once the preload is taken out (whether his way, or by tightening to spec regardless of can lobe position) bottomed out is bottomed out. His additional 1/2 turn accomplishes the same thing as torquing to spec.
Being hydraulic, once the pushrod compresses the lifter all it will compress, the rest is just securing the bolt in place.
Both ways are correct, but "our" way is completely foolproof.
 
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