5.3 lifter valve train noise??
Thread Starter
On The Tree
Joined: Nov 2015
Posts: 171
Likes: 5
5.3 lifter valve train noise?? So I got a 5.3 with custom spec'd cam by Martin Smallwood, he also recommended other stuff which I bought. Upgraded pushrods, morel lifters, dual springs, titanium keepers and retainers, IWIS chain and new hi pressure oil pump. I'm slightly concerned it has a little lifter noise. Running 10w30 oil for its first run drivin a few hours now, was going to change oil today, I know 5w30 was recommended stock. Any ideas? Tips on what else to run?
Oh if it matters. Cam is 228 236 @ 50, .595 .612
Also have the trunion upgrade as well.
Oh if it matters. Cam is 228 236 @ 50, .595 .612
Also have the trunion upgrade as well.
Last edited by parrisw; Jul 11, 2016 at 10:27 AM.
Thread Starter
On The Tree
Joined: Nov 2015
Posts: 171
Likes: 5
Ya I figured the cam would be a little noiser. No I didn't measure. Went with what he recommended. Seems to be about 3/4 turn of preload.
TECH Junkie
Joined: Dec 2012
Posts: 3,615
Likes: 1,327
From: Iowa
Measure and ensure preload. 3/4 turns is less than .040 preload. Not enough imo. With properly adjusted rockers using appropriate pushrods, there shouldn't be any lifter noise, even with aggressive lobes. shoot for 1 1/4 turns (.060) preload.
Thread Starter
On The Tree
Joined: Nov 2015
Posts: 171
Likes: 5
Ok thank you. What's best way to measure? Is counting turns enough?
Here's the way that worked best for me (and many others): https://ls1tech.com/forums/generatio...l#post19085422
Starting on post #13.
Starting on post #13.
The thread pitch on the rocker bolt is 1.25mm or .048", but the ratio is 1.7:1, so the pushrod moves 2.7/1.7 further than the bolt. .048 x 2.7 / 1.7 = .076". I use .075" per bolt rotation for easy math.
[rant]
There is a huge misconception out there that 1 rotation on the rocker bolt is .050. That's for the pushrod checker, NOT THE ROCKER BOLT.
Also, don't count rotations to 22-ft-lbs of torque. When you are torqueing the bolt, you are no longer adding preload - you are actually stretching the bolt.
[/rant]
It's all in the thread that Brew posted. Find dead-soft touch with the rocker bolt - and i mean just barely touching. Then, mark the bolt at 12:00, and use something to turn the bolt by hand, but only until it bottoms out. Don't torque it. Now, look at the clock position. 10:00 is close to .060" preload. Then, if preload is correct, put your torque wrench on and go to 22 ft-lbs.
The thread has pics, etc, which make it pretty easy to follow
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Thread Starter
On The Tree
Joined: Nov 2015
Posts: 171
Likes: 5
Thank you. Yes it's 3/4 I'm sure. I threaded it in till 0 lash then tighten till bolt stopped. No torque.
if you are going from zero lash to tight but not torqued - which is the correct way to measure rotation - 3/4 turn on the bolt is .055" preload.
The thread pitch on the rocker bolt is 1.25mm or .048", but the ratio is 1.7:1, so the pushrod moves 2.7/1.7 further than the bolt. .048 x 2.7 / 1.7 = .076". I use .075" per bolt rotation for easy math.
[rant]
There is a huge misconception out there that 1 rotation on the rocker bolt is .050. That's for the pushrod checker, NOT THE ROCKER BOLT.
Also, don't count rotations to 22-ft-lbs of torque. When you are torqueing the bolt, you are no longer adding preload - you are actually stretching the bolt.
[/rant]
It's all in the thread that Brew posted. Find dead-soft touch with the rocker bolt - and i mean just barely touching. Then, mark the bolt at 12:00, and use something to turn the bolt by hand, but only until it bottoms out. Don't torque it. Now, look at the clock position. 10:00 is close to .060" preload. Then, if preload is correct, put your torque wrench on and go to 22 ft-lbs.
The thread has pics, etc, which make it pretty easy to follow
The thread pitch on the rocker bolt is 1.25mm or .048", but the ratio is 1.7:1, so the pushrod moves 2.7/1.7 further than the bolt. .048 x 2.7 / 1.7 = .076". I use .075" per bolt rotation for easy math.
[rant]
There is a huge misconception out there that 1 rotation on the rocker bolt is .050. That's for the pushrod checker, NOT THE ROCKER BOLT.
Also, don't count rotations to 22-ft-lbs of torque. When you are torqueing the bolt, you are no longer adding preload - you are actually stretching the bolt.
[/rant]
It's all in the thread that Brew posted. Find dead-soft touch with the rocker bolt - and i mean just barely touching. Then, mark the bolt at 12:00, and use something to turn the bolt by hand, but only until it bottoms out. Don't torque it. Now, look at the clock position. 10:00 is close to .060" preload. Then, if preload is correct, put your torque wrench on and go to 22 ft-lbs.
The thread has pics, etc, which make it pretty easy to follow
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