[Z06] Dropped Valve
Thread Starter
1st Gear
Joined: Jun 2012
Posts: 1
Likes: 0
Dropped Valve
2002 Z06 w/ 21K miles.
Cylinder #3 broken exhaust valve spring. Piston hit the plug and damage the spark plug. Also found coolant in cylinder #8. I see that broken valves are a fairly common occurrence based on some of the forum threads. The dealer removed the valve covers and inspected with a boroscope. They said the block looks good and they didn't see any damage to cylinder walls. They want to pull the motor and rebuild. Price was $7176.
They told me the cause of the exhaust valve breaking was when the car is stored for winters and the exhaust valve is the in the elongated position it can develop stress cracks, then under pressure it will snap. Told me that during storage these cars need to be started once a week for 10 minutes. I guess I missed those instruction when I purchased, but none the less I wasn't to pleased. Furthermore, while I don't drive this car in the winter, I don't think it ever sat for more than 8 weeks without being driven.
What reasons have other been given as the cause of all these valve spring breaks? Does this sound like a $7176 repair?
Cylinder #3 broken exhaust valve spring. Piston hit the plug and damage the spark plug. Also found coolant in cylinder #8. I see that broken valves are a fairly common occurrence based on some of the forum threads. The dealer removed the valve covers and inspected with a boroscope. They said the block looks good and they didn't see any damage to cylinder walls. They want to pull the motor and rebuild. Price was $7176.
They told me the cause of the exhaust valve breaking was when the car is stored for winters and the exhaust valve is the in the elongated position it can develop stress cracks, then under pressure it will snap. Told me that during storage these cars need to be started once a week for 10 minutes. I guess I missed those instruction when I purchased, but none the less I wasn't to pleased. Furthermore, while I don't drive this car in the winter, I don't think it ever sat for more than 8 weeks without being driven.
What reasons have other been given as the cause of all these valve spring breaks? Does this sound like a $7176 repair?
Drifting
Joined: Jun 2006
Posts: 1,302
Likes: 4
From: Palo Alto CA
Really common failure on the '02-'03 Z06. Supposedly we all got substandard springs from the factory. Probably 2 reported failures per month on this forum. Very common, and most of us on here replace(d) them. I went with a PAC spring. Some people are lucky and not much goes wrong when they fail, but others have massive damage like you. It probably has nothing to do with what they told you, they are just a ticking time bomb on the cars who got springs from this bad batch.
I have no idea about the quote for a repair, but I would think for that kind of money you might as well get a pretty built up engine. I wouldn't think a stock LS6 would cost that much. I know some people also go with a LS3 or LS7.
Sorry it happened to you, but if you had read these forums with any regularity, you would know this is VERY common. Do a search and see how many others report this happened to them.
I have no idea about the quote for a repair, but I would think for that kind of money you might as well get a pretty built up engine. I wouldn't think a stock LS6 would cost that much. I know some people also go with a LS3 or LS7.
Sorry it happened to you, but if you had read these forums with any regularity, you would know this is VERY common. Do a search and see how many others report this happened to them.
Racer
Joined: May 2012
Posts: 427
Likes: 10
From: Texas
Think I may have been TPS that had GM crate motors on sale, LS3 with 480hp for under $7,000.
Looked back and looks like I was wrong, not TPS, but will keep looking.
Looked back and looks like I was wrong, not TPS, but will keep looking.
Last edited by Titan22; Jun 18, 2012 at 10:40 PM.
Melting Slicks
Joined: Jul 2010
Posts: 3,355
Likes: 113
From: Los Angeles
2002 Z06 w/ 21K miles.
Cylinder #3 broken exhaust valve spring. Piston hit the plug and damage the spark plug. Also found coolant in cylinder #8. I see that broken valves are a fairly common occurrence based on some of the forum threads. The dealer removed the valve covers and inspected with a boroscope. They said the block looks good and they didn't see any damage to cylinder walls. They want to pull the motor and rebuild. Price was $7176.
They told me the cause of the exhaust valve breaking was when the car is stored for winters and the exhaust valve is the in the elongated position it can develop stress cracks, then under pressure it will snap. Told me that during storage these cars need to be started once a week for 10 minutes. I guess I missed those instruction when I purchased, but none the less I wasn't to pleased. Furthermore, while I don't drive this car in the winter, I don't think it ever sat for more than 8 weeks without being driven.
What reasons have other been given as the cause of all these valve spring breaks? Does this sound like a $7176 repair?
Cylinder #3 broken exhaust valve spring. Piston hit the plug and damage the spark plug. Also found coolant in cylinder #8. I see that broken valves are a fairly common occurrence based on some of the forum threads. The dealer removed the valve covers and inspected with a boroscope. They said the block looks good and they didn't see any damage to cylinder walls. They want to pull the motor and rebuild. Price was $7176.
They told me the cause of the exhaust valve breaking was when the car is stored for winters and the exhaust valve is the in the elongated position it can develop stress cracks, then under pressure it will snap. Told me that during storage these cars need to be started once a week for 10 minutes. I guess I missed those instruction when I purchased, but none the less I wasn't to pleased. Furthermore, while I don't drive this car in the winter, I don't think it ever sat for more than 8 weeks without being driven.
What reasons have other been given as the cause of all these valve spring breaks? Does this sound like a $7176 repair?
corvetteforum.com/c5-z06-discussion/build-date-vin-analysis-of-ls6-valve-spring-failures.html
Melting Slicks
Joined: Jul 2010
Posts: 3,355
Likes: 113
From: Los Angeles
Le Mans Master
Joined: Mar 2002
Posts: 5,955
Likes: 161
From: PNW
Would be interested to know the build date of your Zee. Mine could have been a hair away from grenading before I swapped the spring out.
Drifting
Joined: Jan 2008
Posts: 1,722
Likes: 138
From: Florida
St. Jude Donor '09
I would ask if in fact the cylinder wall was not damaged and with only 21K on the clock why are they recommending a complete overhaul. Additionally I would ask if there was any damage to the affected piston and cylinder head that would require replacement of either or both components.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
5 Best & 5 Worst Corvette Daily Drivers
Joe Kucinski
The Headlights of Every Corvette Generation Explained
Joe Kucinski
5 Best & 5 Most Overrated Corvette Track Packages of All Time!
Joe Kucinski
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
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
Heel & Toe
Joined: Jun 2012
Posts: 24
Likes: 1
From: Sierra Vista AZ
I'm really kind of suprised that GM hasn't issued some sort of recall for the springs with the amount of vettes that have been damaged due to these faulty springs.
Burning Brakes
Joined: Jun 2009
Posts: 787
Likes: 1
From: New Baltimore Michigan
[QUOTE=neetstuff55;1581105354]2002 Z06 w/ 21K miles.
Cylinder #3 broken exhaust valve spring. Piston hit the plug and damage the spark plug.
Did the dealer tell you that!!!! If the spark plug is damaged its not from the piston, cant happen ( unless the piston came apart when the valve hit it) probably a bent valve hit it
Steve
Cylinder #3 broken exhaust valve spring. Piston hit the plug and damage the spark plug.
Did the dealer tell you that!!!! If the spark plug is damaged its not from the piston, cant happen ( unless the piston came apart when the valve hit it) probably a bent valve hit it
Steve
Instructor
Joined: Feb 2012
Posts: 137
Likes: 0
From: Las Vegas Nevada
Well, I am currently having my LS6 replaced with a rebuilt one. GM evidently doesn't make the LS6 anymore. It costing me roughly 9500 with everything. Hurts to pay out that much cash for the stealership to do this, but I don't have the facilities or time to do it myself right now. It actually would have cost me more to have the old block repaired and the engine rebuilt than it did to find one through another company and delivered to the dealer to install.
I'm really kind of suprised that GM hasn't issued some sort of recall for the springs with the amount of vettes that have been damaged due to these faulty springs.
I'm really kind of suprised that GM hasn't issued some sort of recall for the springs with the amount of vettes that have been damaged due to these faulty springs.
Heel & Toe
Joined: Jun 2012
Posts: 24
Likes: 1
From: Sierra Vista AZ
Heel & Toe
Joined: Jun 2012
Posts: 24
Likes: 1
From: Sierra Vista AZ
This one is a done deal though, they are about done with it.
Safety Car
Joined: Oct 2004
Posts: 4,816
Likes: 132
From: Plano TX
There were just under 17000 Z06s built for 2002-2003.. There are 130 reports of broken valve springs on those models (this forum).. Thats less than 1%.. Numbers maybe as high as 3-4% are possible.. that would be 510-680 engines with vavle spring failure.. Statistically its very rare to break a spring.. I called 3 local hi volume Corvette speedshops in Dallas and 2 dealerships and asked the question.. Sure enough its almost unheard of.. I still replaced mine just to be safe.. I don't want to be in that 3-4% group..
Drifting
Joined: Jun 2006
Posts: 1,302
Likes: 4
From: Palo Alto CA
There were just under 17000 Z06s built for 2002-2003.. There are 130 reports of broken valve springs on those models (this forum).. Thats less than 1%.. Numbers maybe as high as 3-4% are possible.. that would be 510-680 engines with vavle spring failure.. Statistically its very rare to break a spring.. I called 3 local hi volume Corvette speedshops in Dallas and 2 dealerships and asked the question.. Sure enough its almost unheard of.. I still replaced mine just to be safe.. I don't want to be in that 3-4% group..
Safety Car
Joined: Oct 2004
Posts: 4,816
Likes: 132
From: Plano TX
You need to read my post carefully... 130 reports on this forum which is less than 1%.. 3-4% is more likely(people that do not report failures on this forum..
Burning Brakes
Joined: Jun 2004
Posts: 1,184
Likes: 3
From: KADS- If it has wings or an engine, I can break it. Dallas TX
Another LS6 with a broken valve spring. Welcome to the club. I joined it 2010.
Best of luck with the rebuild.
Don't believe the dealer BS, just a bad batch of springs. I drive my car every week, mine still broke. If the car was stored in COMPRESSED state for that cylinder, it would mean every car that GM built would be breaking springs. if stored more than a couple of weeks. That is some dumb *** mechanic spewing ********, for lack of understanding. I would look for a new mechanic after he said something really stupid such as that.
Best of luck with the rebuild.
Don't believe the dealer BS, just a bad batch of springs. I drive my car every week, mine still broke. If the car was stored in COMPRESSED state for that cylinder, it would mean every car that GM built would be breaking springs. if stored more than a couple of weeks. That is some dumb *** mechanic spewing ********, for lack of understanding. I would look for a new mechanic after he said something really stupid such as that.
Last edited by 2K3Z06; Jun 19, 2012 at 04:28 PM.
Melting Slicks
Joined: Jul 2010
Posts: 3,355
Likes: 113
From: Los Angeles
There were just under 17000 Z06s built for 2002-2003.. There are 130 reports of broken valve springs on those models (this forum).. Thats less than 1%.. Numbers maybe as high as 3-4% are possible.. that would be 510-680 engines with vavle spring failure.. Statistically its very rare to break a spring.. I called 3 local hi volume Corvette speedshops in Dallas and 2 dealerships and asked the question.. Sure enough its almost unheard of..
However, you're averaging across the entire two year period. If my study shows anything, it's that there's a hot spot in the spring and summer of 2002 in which failures are far more prevalent than during other periods of time.
