Morel 5315 lifter preload
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Teching In
Joined: May 2016
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From: Nebraska
Morel 5315 lifter preload So I'm finally venturing past the valve overs of my ls1. Just installed morel 5315 (drop in) lifters. Used eo/ic preload was 1.5 turns so roughly .70 I believe. Tick said they run them at .60 is the extra .1 really going to matter? Double checked with length checker and got 7.375 for a preload of .47. I do have the straub kit but have been torquing to 22ft/lb, since a few mentioned stripping the head if going to the recommended 29ft/lb. if I do get the shorter pushrods should I torque them down more to increase preload? Hope I explained my question correctly I searched but didn't find much info on the morel lifters
Torquing stretches the bolt not increases preload and why I think the "turn method" is bunk. To increase pre-load it would have to be squashing the pedestal. Measure and order the length push rod you need to get your desired pre-load. What you measured my be good enough but be a little noisier.
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Teching In
Joined: May 2016
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From: Nebraska
Forgot about this post the 7.375 did work but I don't feel like the car is breathing like it should I tried it with 7.4 and I got the sewing machine noise. Somewhere in between would have most likely been ideal. The heads are coming back off in the next few weeks so whatever it was a temporary arrangement anyways to get her driving again
That's aint correct. Morel says .060 for the 5315
I am also running the 5315 in my LQ4 with 578 lift. I used the 7.4 pushrod and ended up with about .056 preload. Turn the rocker bolt by hand and as soon as you feel the pushrod start to tighten up when spinning with your fingers, its at zero lash. Then crank the bolt by hand as tight as you can get it until the bolt seats. That's your preload number. I got about .75 turn of the bolt. After that you are just torqueing the bolt and not getting any more preload. I was at .8 to .9 of a full turn to reach full torque at 22lbs.
I am also running the 5315 in my LQ4 with 578 lift. I used the 7.4 pushrod and ended up with about .056 preload. Turn the rocker bolt by hand and as soon as you feel the pushrod start to tighten up when spinning with your fingers, its at zero lash. Then crank the bolt by hand as tight as you can get it until the bolt seats. That's your preload number. I got about .75 turn of the bolt. After that you are just torqueing the bolt and not getting any more preload. I was at .8 to .9 of a full turn to reach full torque at 22lbs.
Yeah, somewhere around .060.
Start here on post #13 for proper measuring instructions: https://ls1tech.com/forums/generatio...l#post19085422
You're trying to combine methods which is the same thing I did at first. Forget 22 ft/lb during the measuring. This guide is basically a more in-depth version of Taxmans post.
Start here on post #13 for proper measuring instructions: https://ls1tech.com/forums/generatio...l#post19085422
You're trying to combine methods which is the same thing I did at first. Forget 22 ft/lb during the measuring. This guide is basically a more in-depth version of Taxmans post.
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Verdad Gallardo That's aint correct. Morel says .060 for the 5315
I am also running the 5315 in my LQ4 with 578 lift. I used the 7.4 pushrod and ended up with about .056 preload. Turn the rocker bolt by hand and as soon as you feel the pushrod start to tighten up when spinning with your fingers, its at zero lash. Then crank the bolt by hand as tight as you can get it until the bolt seats. That's your preload number. I got about .75 turn of the bolt. After that you are just torqueing the bolt and not getting any more preload. I was at .8 to .9 of a full turn to reach full torque at 22lbs.
I am also running the 5315 in my LQ4 with 578 lift. I used the 7.4 pushrod and ended up with about .056 preload. Turn the rocker bolt by hand and as soon as you feel the pushrod start to tighten up when spinning with your fingers, its at zero lash. Then crank the bolt by hand as tight as you can get it until the bolt seats. That's your preload number. I got about .75 turn of the bolt. After that you are just torqueing the bolt and not getting any more preload. I was at .8 to .9 of a full turn to reach full torque at 22lbs.
BUT, the preload on the lifter is actually 2.7/1.7 or 1.588 times further than the bolt moves, because it's a lever, and the valve side is fixed when you're preloading the lifter. .049 x 1.588 = .078 is how much preload you get on one turn of the bolt.
There's a lot of misunderstanding out there, because the instructions from some will say "torque the bolt to 22-ft-lbs, and at .070 preload, it'll rotate 1-1/4 to 1-1/2 turns." Where that comes from is the actual stretching of the bolt due to application of torque, and the extra rotation does not contribute to preload. Partially stretching the bolt causes it to act like a spring, and its desire to return to its original length is what actually provides the clamping force
if you do it in stages - first find dead soft touch for exactly zero lash. Then tighten the bolt until it needs force but don't actually torque it. Measure that amount of rotation, that's your preload. Then, torque the bolt, and you'll typically gain another 180 degrees rotation.
That makes sense...thanks! I am going to recheck my push rod length this weekend. When I measured them I came up with 7.265, added .060 for preload which gives me a 7.325 end to end. When I bought push rods I did not realize that most are measured gauge length, so I am thinking I might be .017 light from where I wanted to be.
Yea, when I did took my measurements with an pushrod checker, I also ended up needing a 7.325 which would give me .050 preload. I then checked it the old fashion way by using the method I and Darth explained and it came out like mentioned. The 7.325 would have been too short.
You could also put a dial indicator on top of the rocker above the pushrod and use it to measure the drop or preload you are getting. It would be really close and accurate enough.
You could also put a dial indicator on top of the rocker above the pushrod and use it to measure the drop or preload you are getting. It would be really close and accurate enough.
Last edited by Taxman20; Aug 31, 2016 at 02:33 PM.
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From: Monroe,NY
That makes sense...thanks! I am going to recheck my push rod length this weekend. When I measured them I came up with 7.265, added .060 for preload which gives me a 7.325 end to end. When I bought push rods I did not realize that most are measured gauge length, so I am thinking I might be .017 light from where I wanted to be.
Yes I said that wrong. What I am saying is some companies pushrods measure shorter end to end compared to advertised length. I had a set of TSP 7.4 push rods that I initially bought with my cam and they measured 7.385 If I remember correctly. I should of measured these Manleys end to end and checked the turns when installing them.
The engine runs great and is quiet except when it gets up to full temp then the oil psi drops off a little and I get some sewing machine noise in the 1500-2000rpm range under light load.
Everything I have read tells me that is 1) normal 2) the push rods might be a hair short.
So for piece of mind I am going to double check it just to see because you could ask 10 knowledgeable people on the subject and its a 50/50 split on being normal or incorrect push rod length.
The engine runs great and is quiet except when it gets up to full temp then the oil psi drops off a little and I get some sewing machine noise in the 1500-2000rpm range under light load.
Everything I have read tells me that is 1) normal 2) the push rods might be a hair short.
So for piece of mind I am going to double check it just to see because you could ask 10 knowledgeable people on the subject and its a 50/50 split on being normal or incorrect push rod length.
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You're looking at the bolt and not the travel at the cup of the rocker. Ont he bolt, the thread pitch is 1.25mm, so one turn of the bolt lowers the center of the rocker .0.49".
BUT, the preload on the lifter is actually 2.7/1.7 or 1.588 times further than the bolt moves, because it's a lever, and the valve side is fixed when you're preloading the lifter. .049 x 1.588 = .078 is how much preload you get on one turn of the bolt.
There's a lot of misunderstanding out there, because the instructions from some will say "torque the bolt to 22-ft-lbs, and at .070 preload, it'll rotate 1-1/4 to 1-1/2 turns." Where that comes from is the actual stretching of the bolt due to application of torque, and the extra rotation does not contribute to preload. Partially stretching the bolt causes it to act like a spring, and its desire to return to its original length is what actually provides the clamping force
if you do it in stages - first find dead soft touch for exactly zero lash. Then tighten the bolt until it needs force but don't actually torque it. Measure that amount of rotation, that's your preload. Then, torque the bolt, and you'll typically gain another 180 degrees rotation.
BUT, the preload on the lifter is actually 2.7/1.7 or 1.588 times further than the bolt moves, because it's a lever, and the valve side is fixed when you're preloading the lifter. .049 x 1.588 = .078 is how much preload you get on one turn of the bolt.
There's a lot of misunderstanding out there, because the instructions from some will say "torque the bolt to 22-ft-lbs, and at .070 preload, it'll rotate 1-1/4 to 1-1/2 turns." Where that comes from is the actual stretching of the bolt due to application of torque, and the extra rotation does not contribute to preload. Partially stretching the bolt causes it to act like a spring, and its desire to return to its original length is what actually provides the clamping force
if you do it in stages - first find dead soft touch for exactly zero lash. Then tighten the bolt until it needs force but don't actually torque it. Measure that amount of rotation, that's your preload. Then, torque the bolt, and you'll typically gain another 180 degrees rotation.
I can't explain how many times I've had to correct people on using bolt turns for pre-load and why using the thread pitch is not an accurate way of doing do. Also probably inflates the number of true lifter failures, the internet gospel has people nearly doubling their pre-load.
Do it right and use a dial indicator on the PR.
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Will somebody splan what exactly the preload is.
Is it how deep in the lifter you want the pushrod?
Is that half of the travel of the plunger travel inside the lifter?
Where do you idealy want the pushrod to be as far as the travel of the plunger inside of
the lifter?
Is it how deep in the lifter you want the pushrod?
Is that half of the travel of the plunger travel inside the lifter?
Where do you idealy want the pushrod to be as far as the travel of the plunger inside of
the lifter?
