Generation III External Engine LS1 | LS6 | Bolt-Ons | Intakes | Exhaust | Ignition | Accessories
Sponsored by:
Sponsored by:

Slinging Drive belt "normal"?

Thread Tools
 
Search this Thread
 
Old Dec 2, 2010 | 02:44 PM
  #1  
357i's Avatar
Thread Starter
10 Second Club
iTrader: (4)
 
Joined: Sep 2009
Posts: 204
Likes: 1
From: Richmond, VA
Default Slinging Drive belt "normal"?

In the 2000 or so miles since I have been running my engine after the rebuild, I have thrown the serpentine belt off 2 times. The first time was after about 800 miles and the second time was at the dragstrip about 60 miles ago. I have never owned an LSx motor before this one. Both times I was able to recover the belt. There are no nicks or notches in it at all and it apears to be in perfect shape, no wear on the edges like a pulley miss alignment. I found that there are a few companys that sell a manual tensioner with a larger "lip" on the pulley that is suposed to solve this problem. The companys make this out to be a common problem with the gen 3/4 engines, but I have never heard about it on here. FYI, I do turn the engine 6500rpm.

http://store.katechengines.com/bille...sioner-p2.aspx

Thank you for your opinins
Reply
Old Dec 2, 2010 | 03:26 PM
  #2  
TooLateVTEC's Avatar
TECH Fanatic
iTrader: (2)
 
Joined: Apr 2009
Posts: 1,445
Likes: 2
From: FredVegas, Va
Default

Well, im not sure about it being normal but its possible. Are the pulleys in any factory configuration? If not, than they may be out of alignment just enough to throw the belt and not noticeable to the naked eye.

Also, once a belt has been thrown off its basically no good and will get thrown off much easier the 2nd time.
Reply
Old Dec 2, 2010 | 03:38 PM
  #3  
LS6427's Avatar
Banned
iTrader: (2)
 
Joined: May 2008
Posts: 11,289
Likes: 13
From: South Florida
Default

YES.........its 100% normal.

If you are modded with just a medium amount of HP increase you will throw the belt when you wack the throttle. The factory (JUNK DESIGN) belt tensioner bounces too rapidly and the belt comes off. That Katech tensioner is what you need, it 100% soves the problem. When I got my 427ci put in I threw my belt about 8 times in one week until someone told me about the problem. I got the Katech and its been 8 years......with no tossed belt.

Thats another thing.........the factory tensioner allows the belt to bounce.....which in turn allows the belt to stretch over time. The Katech tensioner doesn't allow the belt to bounce one single bit, which resists or greatly reduces stretching.

I just changed my belt like a month ago....it was 8+ years old when I put my Katech tensioner on. Your belt will last until its starts to fall apart from age before it stretches.

With the factory tensioner that bounces...when you put a new belt on you can look at the indicator....its nice and tight. Then just a few months later you can see the indicator mark on the tensioner has moved already. Bouncing kills belts.

Get the Katech tensioner.

(Disclaimer...I'm sure there are people with modded engines that use their factory tensioners and DO NOT throw belts.......alot of guys just have that problem when they start modding. Katech solves it 100% for those of us that do lose belts.)


.
Reply
Old Dec 2, 2010 | 03:47 PM
  #4  
357i's Avatar
Thread Starter
10 Second Club
iTrader: (4)
 
Joined: Sep 2009
Posts: 204
Likes: 1
From: Richmond, VA
Default

The pulleys are all factory Fbody pulleys in the stock Fbody locations.

Thanks for the info
Reply
Old Dec 2, 2010 | 09:01 PM
  #5  
1madss's Avatar
TECH Resident
20 Year Member
iTrader: (10)
 
Joined: Nov 2001
Posts: 768
Likes: 2
From: Spring Hill TN
Default

How old is the stock tensioner? My H/C LS1 would start to fling the belt anytime I got over 5K rpm once the tensioner would get 40-50K miles on it. A new tensioner always fixed it for a while. I have a Katech now.
Reply
Old Dec 2, 2010 | 11:17 PM
  #6  
01ssreda4's Avatar
TECH Senior Member
15 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (96)
 
Joined: Aug 2007
Posts: 24,241
Likes: 89
From: Turnin' Wrenches Infractions: 005
Default

Buy a new tensioner from the auto parts store. Problem solved. The springs in them weaken with age and they don't function properly anymore.
Reply
Old Dec 3, 2010 | 08:21 AM
  #7  
jam01's Avatar
TECH Enthusiast
 
Joined: Feb 2005
Posts: 734
Likes: 0
From: south jersey. again
Default

no it is not normal at all, it is usually caused by misaligned and or bent or bad pulley's a bad or worn belt. while added hp will increase the chances of throwing a belt which is why gm made deep groove pulleys for higher hp engines way back when. this is also why the aftermarket makes parts and accessories, the katech tensioner should help you.

and contrary to some opinions the factory stuff is fine for most applications.
Reply
Old Dec 3, 2010 | 10:31 AM
  #8  
Jon@Texas-Speed's Avatar
FormerVendor
iTrader: (18)
 
Joined: Sep 2004
Posts: 3,043
Likes: 2
From: Lubbock, TX
Default

Double check the alignment. If it looks good, throw a Katech tensioner on there and you will be set!

Jon
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




All times are GMT -5. The time now is 09:54 PM.

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