Pushrod length question
Pushrod length question Lifters are LS7 lifters. The bulk ones that used to be on WS6store.
Now, I previously had 7.375 pushrods, before all the rebuild stuff. Now, the engine runs, seems to pull well, but there is kind of a ticking / sewing machine sound and it annoys me a lot.
I decided to attempt to measure the pushrod length while it has normal dual springs in it. I can't get my fingers in to turn it while it's in. But, 9 turns is too loose, and 10 turns is too tight. So, this would be between 7.25 and 7.3, right? at 7.25, there is a little, motion, not much. at 7.3, it's preloading a little. So, 'between', I could say 7.275 or so.
Now... i have 7.375 in there. That would give me around .1" preload, right?
When I tighten / torque down the rocker with the 7.375 rod, I see the valve spring compress some.
I took a dial gauge and setup to look at retainer height. I tighten down the rocker, and see it compress, dial gauge spins about 1.5x. Then, if I watch it, it slowly spins back to the original spot, but it takes ~30-40 seconds to get back to the original spot.
Does this seem normal? And, is the .1" preload too much? Feeling kind of like grabbing 7.35 rods... ?
Now, I previously had 7.375 pushrods, before all the rebuild stuff. Now, the engine runs, seems to pull well, but there is kind of a ticking / sewing machine sound and it annoys me a lot.
I decided to attempt to measure the pushrod length while it has normal dual springs in it. I can't get my fingers in to turn it while it's in. But, 9 turns is too loose, and 10 turns is too tight. So, this would be between 7.25 and 7.3, right? at 7.25, there is a little, motion, not much. at 7.3, it's preloading a little. So, 'between', I could say 7.275 or so.
Now... i have 7.375 in there. That would give me around .1" preload, right?
When I tighten / torque down the rocker with the 7.375 rod, I see the valve spring compress some.
I took a dial gauge and setup to look at retainer height. I tighten down the rocker, and see it compress, dial gauge spins about 1.5x. Then, if I watch it, it slowly spins back to the original spot, but it takes ~30-40 seconds to get back to the original spot.
Does this seem normal? And, is the .1" preload too much? Feeling kind of like grabbing 7.35 rods... ?
TECH Fanatic
Joined: Jan 2018
Posts: 1,251
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From: Dade City, Fl.
Read this article I would measure at least an intake and exhaust length on both banks. When I did my setup I measured all positions, but the engine was on a stand...way easier
. If you are having trouble reaching in to spin the checker to make it longer, take the rocker off and adjust the length of the checker, re-install rocker etc... takes longer but you'll get it right. Scoggin-Dickey video
. If you are having trouble reaching in to spin the checker to make it longer, take the rocker off and adjust the length of the checker, re-install rocker etc... takes longer but you'll get it right. Scoggin-Dickey video 
