Generation III Internal Engine 1997-2006 LS1 | LS6
Sponsored by:
Sponsored by:

Knocking but from what?

Thread Tools
 
Search this Thread
 
Old Nov 15, 2015 | 09:30 PM
  #1  
j8o's Avatar
j8o
Thread Starter
Teching In
 
Joined: Sep 2015
Posts: 5
Likes: 0
Default Knocking but from what?

Ls1
243 heads
Vrx4 cam
BTR pushrods 7.375 length
Just replaced ls1 lifters with ls7 lifters


Ran great for about an hour at idle. Took it to the road and was leaving a stop light after about 5 miles of driving and now it is knocking again. Any ideas guys?
Reply
Old Nov 15, 2015 | 09:39 PM
  #2  
j8o's Avatar
j8o
Thread Starter
Teching In
 
Joined: Sep 2015
Posts: 5
Likes: 0
Default

https://youtu.be/Fcbd37UiHQ4
Reply
Old Nov 15, 2015 | 09:40 PM
  #3  
j8o's Avatar
j8o
Thread Starter
Teching In
 
Joined: Sep 2015
Posts: 5
Likes: 0
Default

https://youtu.be/Fcbd37UiHQ4http://https://youtu.be/Fcbd37UiHQ4
Reply
Old Nov 15, 2015 | 10:43 PM
  #4  
kinglt-1's Avatar
TECH Senior Member
20 Year Member
Liked
Loved
Community Favorite
iTrader: (26)
 
Joined: Jul 2005
Posts: 5,894
Likes: 254
From: Ft. Wayne, IN
Default

Reply
Old Nov 15, 2015 | 11:09 PM
  #5  
subeone's Avatar
TECH Fanatic
10 Year Member
iTrader: (5)
 
Joined: Apr 2013
Posts: 1,317
Likes: 93
Default

check your rockers for play
Reply
Old Nov 15, 2015 | 11:13 PM
  #6  
molotov004's Avatar
Teching In
 
Joined: Feb 2015
Posts: 13
Likes: 0
Default

did you check your oil pressure?
Have you lost oil pressure, does your oil pressure go up or down when you
press the gas pedal?
Reply
Old Nov 16, 2015 | 05:47 AM
  #7  
j8o's Avatar
j8o
Thread Starter
Teching In
 
Joined: Sep 2015
Posts: 5
Likes: 0
Default

Has good oil pressure and yes goes up and down with pressing the gas. About 40lbs at idle
Reply
Old Nov 16, 2015 | 06:31 AM
  #8  
RockinWs6's Avatar
TECH Addict
 
Joined: Mar 2013
Posts: 2,628
Likes: 30
Default

Unfortunately you either had a lifter roller seize OR you spun a rod bearing. Both sound similar. Either way you need to open it up. From here I'd say you lost a rod bearing.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo
Old Nov 16, 2015 | 09:50 PM
  #9  
the404man's Avatar
On The Tree
 
Joined: Jun 2012
Posts: 122
Likes: 2
Default

Originally Posted by RockinWs6
Unfortunately you either had a lifter roller seize OR you spun a rod bearing. Both sound similar. Either way you need to open it up. From here I'd say you lost a rod bearing.
What he said ^^^^^
Reply
Old Nov 16, 2015 | 10:09 PM
  #10  
j8o's Avatar
j8o
Thread Starter
Teching In
 
Joined: Sep 2015
Posts: 5
Likes: 0
Default

Originally Posted by the404man
What he said ^^^^^
I JUST replaced the ls1 lifters with LS7 lifters. Like less than 10 miles before this happened. Do you think it could be a lifter roller that seized for whatever reason or mostly a rod bearing. I don't have much time to take it apart so when I do I want to start in the right place lol
Reply
Old Nov 16, 2015 | 10:18 PM
  #11  
Russ K's Avatar
TECH Resident
20 Year Member
Photogenic
Photoriffic
Liked
iTrader: (1)
 
Joined: Apr 2006
Posts: 811
Likes: 4
From: Regina, Sask
Default

That is a rod bearing knock, and the squeaking noise is the piston hitting the cyl head.

Russ Kemp
Reply
Old Nov 17, 2015 | 10:21 PM
  #12  
the404man's Avatar
On The Tree
 
Joined: Jun 2012
Posts: 122
Likes: 2
Default

Originally Posted by j8o
I JUST replaced the ls1 lifters with LS7 lifters. Like less than 10 miles before this happened. Do you think it could be a lifter roller that seized for whatever reason or mostly a rod bearing. I don't have much time to take it apart so when I do I want to start in the right place lol
Take one plug wire off at a time until the sound changes or stops, then you will know if its rod knock if the sound changes or stops, if not, then you can go with removing the valve covers one side at a time and then pick which cylinder you want to start with and do one at a time take the rocker off and push rod out for each valve one at a time, start engine, and replace and repeat until the sound is gone, once gone you will know if its a lifter, im saying rod but hope its a lifter man..

O and get a large piece of cardboard or something to catch/ reflect the oil for when starting the engine with the valve cover off . !

hope that makes sense .. im totally tired right now.. please someone correct me if you see the error im off to bed !

you know its hard to tell really as video cams dont pick out the sound correctly but the more i listen to it, it kinda sounds like a lifter.. sorry man idk really, but you can find out really quick by doing the above, but here is my flat spotted lifter sound ..

Last edited by the404man; Nov 17, 2015 at 10:41 PM. Reason: rocker and push rod, im off to bed
Reply
Old Nov 17, 2015 | 10:32 PM
  #13  
01WS6/tamu's Avatar
TECH Senior Member
20 Year Member
iTrader: (37)
 
Joined: Oct 2004
Posts: 5,121
Likes: 74
From: somewhere in TX
Default

Its screwed spun a rod bearing possibly main sounds like rod a main is a deep heavy clunk rod sounds like your video. That squeak is kiss of death shes done time for a new motor.
Reply




All times are GMT -5. The time now is 07:43 AM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE