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

Cam bearngs

Thread Tools
 
Search this Thread
 
Old Mar 30, 2010 | 07:27 AM
  #1  
Auto Concepts's Avatar
Thread Starter
Teching In
 
Joined: Jun 2008
Posts: 7
Likes: 0
Default Cam bearngs

I have a customers 2000 Vette in my shop. It's a Lingenfelter 403 C.I. twin turbo conversion. He lost oil pressure. I pulled the engine and tore it down. The #2 cam bearing is wiped out and was back far enough to expose the oil grove in the block and wear a notch in it from the lifter. It doesn't look like it spun and when I removed it, there was plenty of press fit. The pistons are scuffed bad on the skirts. The rest of the engine looks good. The crank is perfect. Rod bearings show minor wear. Any ideas what could have caused it. I would like to find the cause to prevent it from happening again.
Thanks
Bob
Reply
Old Mar 30, 2010 | 07:55 AM
  #2  
oange ss's Avatar
TECH Junkie
20 Year Member
iTrader: (50)
 
Joined: Jan 2005
Posts: 3,241
Likes: 6
From: Texas
Default

I'm sure the 2 turbos werent helping matters
Reply
Old Mar 30, 2010 | 08:25 AM
  #3  
89LS1RS's Avatar
Launching!
iTrader: (1)
 
Joined: Jun 2008
Posts: 210
Likes: 0
From: Chicago, illinois
Default

how many miles did the engine make it? did anyone change cams recently? maybe it got bumped and pushed back on install? otherwise it walked from the vibrations once it wiped out, and the 2 turbos probably put a big strain on the oil system. make sure its got a good oil pump and maybe go dry sump so the engine wont starve. the turbos take up oil capacity once everythings running, some people have issues with oil psi dropping under decel, depending on baffling in the pan. add in the lower volume of oil if its not factored in, and once in a while it might starve. had that problem in a olds 455.
Reply
Old Mar 30, 2010 | 02:30 PM
  #4  
HotSilverBird's Avatar
Banned
 
Joined: Mar 2010
Posts: 334
Likes: 3
Default

same thing here http://www.ls1.com/forums/showthread.php?t=14784
Reply
Old Mar 30, 2010 | 03:37 PM
  #5  
HotSilverBird's Avatar
Banned
 
Joined: Mar 2010
Posts: 334
Likes: 3
Default

I've heard of this before, do a search on this site. I know this sounds like a patch but i would use locktite on the cam bearings to be sure they don't move in high HP ls1 applications. Do you have pics of the cam bearing? If it was wiped out could it have been fitted too tight in the 1st place and overheated?
Reply
Old Mar 30, 2010 | 03:39 PM
  #6  
Auto Concepts's Avatar
Thread Starter
Teching In
 
Joined: Jun 2008
Posts: 7
Likes: 0
Default

Originally Posted by HotSilverBird
Sounds like the same problem. I'm a little paranoid about putting this thing together without knowing what caused it. There must be others.
Reply
Old Mar 30, 2010 | 03:46 PM
  #7  
Auto Concepts's Avatar
Thread Starter
Teching In
 
Joined: Jun 2008
Posts: 7
Likes: 0
Default

Originally Posted by HotSilverBird
I've heard of this before, do a search on this site. I know this sounds like a patch but i would use locktite on the cam bearings to be sure they don't move in high HP ls1 applications. Do you have pics of the cam bearing? If it was wiped out could it have been fitted too tight in the 1st place and overheated?
The bearing that moved was wiped out. Over .015 clearance. The only thing I can come up with is that once the bearing wears out, the cam flops around enough to pound on it and work it out.
Reply
Old Mar 30, 2010 | 03:47 PM
  #8  
Auto Concepts's Avatar
Thread Starter
Teching In
 
Joined: Jun 2008
Posts: 7
Likes: 0
Default

Originally Posted by HotSilverBird
I've heard of this before, do a search on this site. I know this sounds like a patch but i would use locktite on the cam bearings to be sure they don't move in high HP ls1 applications. Do you have pics of the cam bearing? If it was wiped out could it have been fitted too tight in the 1st place and overheated?

I'll try and get some pictures posted.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

6 Gifts Neither Your Dad Nor Grad Will Shove Into the 'Trinket Drawer'

 Brett Foote
story-1

Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

 Pouria Savadkouei
story-2

Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

 Verdad Gallardo
story-3

7 Most Reliable High-Performance Engines GM Has Ever Built

 Verdad Gallardo
story-4

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

 Verdad Gallardo
story-5

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

 Pouria Savadkouei
story-6

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

 Verdad Gallardo
story-7

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-8

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-9

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
Old Mar 30, 2010 | 05:15 PM
  #9  
HotSilverBird's Avatar
Banned
 
Joined: Mar 2010
Posts: 334
Likes: 3
Default

Originally Posted by Auto Concepts
The bearing that moved was wiped out. Over .015 clearance. The only thing I can come up with is that once the bearing wears out, the cam flops around enough to pound on it and work it out.
I think once its wore thin they move easily out of place. But honestly I think there is something else going on with these aluminum blocks with the cam bearings walking. I personally have used the locktite to keep bearings in place, if they move with locktite on them something has to be extremely wrong.

Did you check the bore alignment? maybe the block has a core shift. This will cause hell on the bearings but the mains would fail too.

Last edited by HotSilverBird; Mar 30, 2010 at 05:22 PM.
Reply
Old Mar 31, 2010 | 06:05 AM
  #10  
Auto Concepts's Avatar
Thread Starter
Teching In
 
Joined: Jun 2008
Posts: 7
Likes: 0
Default

Originally Posted by HotSilverBird
I think once its wore thin they move easily out of place. But honestly I think there is something else going on with these aluminum blocks with the cam bearings walking. I personally have used the locktite to keep bearings in place, if they move with locktite on them something has to be extremely wrong.

Did you check the bore alignment? maybe the block has a core shift. This will cause hell on the bearings but the mains would fail too.
The cam bore alignment is good and there's no damage to the main bearings. Since aluminum expands more than iron, could the cam bore get large enough to take away most of the press fit when the temp gets high. I do plan on using locktite. The engine doesn't show signs of overheating. It's a PITA getting the engine out and I only want to do this once. Thanks for the help, it's always good to hear other thoughts.
Reply
Old Mar 31, 2010 | 07:42 AM
  #11  
Roy V.'s Avatar
On The Tree
iTrader: (1)
 
Joined: Jul 2005
Posts: 108
Likes: 0
Default

Bob,

Do you know or have you measured the #2 cam bearing bore diameter and the cam journal diameter(s)?

Journal diameter 2.164-2.166 per GM specs.

Bottom of page 93 gives Clevite's specs:

http://mahleclevite.com/publications/EB-10-07.pdf

Bearing mfr. and part #?

Roy

Last edited by Roy V.; Mar 31, 2010 at 09:11 AM.
Reply




All times are GMT -5. The time now is 08:13 AM.

story-0
6 Gifts Neither Your Dad Nor Grad Will Shove Into the 'Trinket Drawer'

Don't get dad new socks or a grill brush this year.

By Brett Foote | 2026-06-09 14:55:56


VIEW MORE
story-1
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

Slideshow: We take a close look at the ONE and Artidiag 800BT2 diagnostic tools from Topdon and the reasons to buy one over the other.

By Pouria Savadkouei | 2026-05-28 11:05:11


VIEW MORE
story-2
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

Slideshow: The controversial Ferrari F6 swaps its original flat-12 for a Corvette Z06-derived LT4 V8 and sends power to four rear wheels through a custom-built drivetrain.

By Verdad Gallardo | 2026-05-26 18:23:54


VIEW MORE
story-3
7 Most Reliable High-Performance Engines GM Has Ever Built

Slideshow:These GM engines didn't just make huge power, they survived abuse, boost, track days, and six-digit mileage with a reputation for refusing to quit.

By Verdad Gallardo | 2026-05-21 16:45:27


VIEW MORE
story-4
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-5
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-6
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-7
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-8
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-9
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