Crank pulley bolt backing out
Thread Starter
Instructor
Joined: Nov 2008
Posts: 237
Likes: 0
From: saint louis mo
Crank pulley bolt backing out
I was attending a track day yesterday and the bolt from the crank pulley backed out and was only stopped by the suspension rack that is in front of the crank pulley. Should I purchase a new crank pulley or should I just torque this one down because I know there is sealant that hoes between the bolt. Thanks for reading.
Last edited by muskaroxs; Aug 30, 2009 at 11:04 PM.
Safety Car
Joined: Feb 2007
Posts: 4,684
Likes: 107
From: Opelika Alabama
if it under warr. let the dealer fix it, if not, as long as the pulley is not damaged. get a new bolt and diamond washer{it comes with the bolt} and tq it down. you might also consider some thread locker, I don't know what sealant your talking about
Thread Starter
Instructor
Joined: Nov 2008
Posts: 237
Likes: 0
From: saint louis mo
Would the dealer fix this because there is a TSB for this problem even though I'm not the original owner? It's a 2005
Last edited by muskaroxs; Aug 30, 2009 at 11:14 PM.
Safety Car
Joined: Feb 2007
Posts: 4,684
Likes: 107
From: Opelika Alabama
Le Mans Master
Joined: Dec 2004
Posts: 5,493
Likes: 808
From: West coast CA
I was attending a track day yesterday and the bolt from the crank pulley backed out and was only stopped by the suspension arm that is in front of the crank pulley. Should I purchase a new crank pulley or should I just torque this one down because I know there is sealant that hoes between the bolt. Thanks for reading.
GM is very clear: do NOT re-use the bolt. The official procedure involves 1) pressing the pulley onto the crank, 2) torquing the OLD bolt to 240 lb.-ft., and then 3) installing a NEW bolt, torquing it to ... something light (look it up) and then turning the bolt it another 140 degrees. It's during the 140 degree part that the bolt is presumably tightened to yield. So the next time you do it, you'll need a new bolt.
Thread Starter
Instructor
Joined: Nov 2008
Posts: 237
Likes: 0
From: saint louis mo
That "suspension arm" is the steering rack.
GM is very clear: do NOT re-use the bolt. The official procedure involves 1) pressing the pulley onto the crank, 2) torquing the OLD bolt to 240 lb.-ft., and then 3) installing a NEW bolt, torquing it to ... something light (look it up) and then turning the bolt it another 140 degrees. It's during the 140 degree part that the bolt is presumably tightened to yield. So the next time you do it, you'll need a new bolt.
GM is very clear: do NOT re-use the bolt. The official procedure involves 1) pressing the pulley onto the crank, 2) torquing the OLD bolt to 240 lb.-ft., and then 3) installing a NEW bolt, torquing it to ... something light (look it up) and then turning the bolt it another 140 degrees. It's during the 140 degree part that the bolt is presumably tightened to yield. So the next time you do it, you'll need a new bolt.
Safety Car
Joined: Jun 1999
Posts: 3,570
Likes: 3
From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
A recall and TSB are two different things.
I am pretty sure a recall means there IS a problem related to safety or emissions and you need to have the dealer check it out because of the serious nature. These generally are handled even if the warranty has expired.
A TSB (Technical Service Bulletin) is a memo to the service tech that if a car comes in with a particular problem, this is what may be wrong and how to fix it. Its not a recall. Just a heads up to the technical service staff. I could be a minor issue and not necessarily covered after expiration of the warranty.
If someone is with a dealership service staff, please comment here.
I am pretty sure a recall means there IS a problem related to safety or emissions and you need to have the dealer check it out because of the serious nature. These generally are handled even if the warranty has expired.
A TSB (Technical Service Bulletin) is a memo to the service tech that if a car comes in with a particular problem, this is what may be wrong and how to fix it. Its not a recall. Just a heads up to the technical service staff. I could be a minor issue and not necessarily covered after expiration of the warranty.
If someone is with a dealership service staff, please comment here.
Last edited by Mez; Sep 1, 2009 at 10:29 PM.
Instructor
Joined: Aug 2007
Posts: 190
Likes: 0
From: Costa Mesa Ca
When mine went, the belts shredded off. GMPP covered everything except the underhood liner which is a "body part" that was damaged by the shredding belts.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Burning Brakes
Joined: Jan 2008
Posts: 905
Likes: 0
From: BURTON MI
They will be happy to fix it for you. But they will charge you unless you are still under warranty in which case it will be free.
When mine went, the belts shredded off. GMPP covered everything except the underhood liner which is a "body part" that was damaged by the shredding belts.
When mine went, the belts shredded off. GMPP covered everything except the underhood liner which is a "body part" that was damaged by the shredding belts.
Melting Slicks
Joined: Mar 2008
Posts: 2,835
Likes: 5
From: Avon Park FLORIDA
St. Jude Donor '08-'09-'10
CF Senior Member
Joined: Feb 2006
Posts: 23,313
Likes: 25
From: Tucson Arizona
You can't reuse the torque-to-yield bolt or it'll be destined to fail. Why GM ever abandoned the keyway I'll never know but all the Gen III and Gen IV V8 engines use a press-fit damper with no keyway. This has been the case since the LS1 was introduced in 1997.
I didn't notice but if your car is an early 2005 I'd make sure you have the 'newer' press-fit harmonic dampener with the friction washer. The friction washer became a production part in the 2006 LS2 and LS7 and I suspect in the later model 2005's as well.
Although the best solution would be to pin the crank (with forced induction applications pinning the crank is essential) IMO if it's put back together correctly using new torque-to-yield bolts, the press-fit damper with the friction washer you should be fine. Good luck!
They're special torque-to-yield bolts and although you ultimately use one...I believe you need two (2) bolts to torque and set it properly.
I didn't notice but if your car is an early 2005 I'd make sure you have the 'newer' press-fit harmonic dampener with the friction washer. The friction washer became a production part in the 2006 LS2 and LS7 and I suspect in the later model 2005's as well.
Although the best solution would be to pin the crank (with forced induction applications pinning the crank is essential) IMO if it's put back together correctly using new torque-to-yield bolts, the press-fit damper with the friction washer you should be fine. Good luck!
They're special torque-to-yield bolts and although you ultimately use one...I believe you need two (2) bolts to torque and set it properly.
Race Director
Joined: Jun 2005
Posts: 10,909
Likes: 2,701
From: Phila Suburbs 2023 C8 & 2013 650ix
Team Owner
Joined: Feb 2000
Posts: 53,529
Likes: 77
From: Arizona
I just had my almost 5 year old '05 done a few weeks ago prophylactically, but I bought three years more of extended warranty.
I would bet that GM would fix it for you if you're under the 11039 VIN, make real nice or pay off your guy at the dealership.
I had stuff done on my C5 after the standard warranty was up. Many of these engineering defects can have a longer, less advertised warranty.
I would bet that GM would fix it for you if you're under the 11039 VIN, make real nice or pay off your guy at the dealership.
I had stuff done on my C5 after the standard warranty was up. Many of these engineering defects can have a longer, less advertised warranty.
Le Mans Master
Joined: Dec 2004
Posts: 5,493
Likes: 808
From: West coast CA
Mine backed out 1/4 inch August 9 th. Broke both belts and damaged the balancer. Because I had a cam change, that bolt was removed and replaced by my tuner, therefore it was not covered by warranty. Dealer was very polite about it. 6 1/2 hrs labor, 2 belts, new bolt ($5.41), 2 gallons anti freeze, ect. $1104.00. Service manager said my tuner didn't torque it properly, and possible reused the old bolt, gave me $150.00 break. My cost $954. I was not happy about that. The mechanic told me GM policy was to torque a new bolt to 240 #, inset a new bolt, torque to 30# then go I think he said 270 deg. (3/4 turn) The end result is more than 240#. Make sure you use two new bolts. Good luck.
140 degrees requires an amazing amount of effort. Over 500 lb.-ft.
Burning Brakes
Joined: Jan 2008
Posts: 905
Likes: 0
From: BURTON MI
I'll buy that. Makes complete sense. I just noticed on my invoice, they charged me for for 1 bolt. $5.41. I said "I think he said" for a reason as I was not sure, but he did say to torque it to 240 then torque the new one to 30# and like you say, another 140 deg. And like you said, the first procedure is to seat the pulley. The GM mechanic said to get to 140, the torque was more the 240#. My tuner apparently didn't torque my bolt properly.
