[Z06] I am depressed - needle bearings on magnetic drain plug
03-28-2008, 07:41 PM
#1
Racer
Thread Starter
needle bearings on magnetic drain plug
I took my car in for the "Service Charging System" and shifter rattle and oil change (3797 miles)... and they found needle bearings from rocker arms on the magnetic drain plug... GM has authorized teardown of engine...
I guess at least the rocker arm did not break completely and break the valve spring and drop the valve into the engine and break the engine...
I really love my silver Z06, but this is very depressing...
I am planning to keep this car a long time and was going to extend my warranty before the base waranty is up (3y/36K?), but now I do not know...
Kristoffer
Edit: BTW, this car has not been abused... I have always been living by the no WOT or over 3500 rpm until oil temp over 150F, and have only done one autox after the break in period and no track time... and the car is completely stock (no tune or other mods)...
Update 3/31/08:
One intake rocker arm broken on each side, on the rear most cylinders, #7 and #8.
BTW, in the pictures the broken ones are just loosely placed back on engine.
Update 4/2/08:
The dealer has received the 2 rocker arms and they are being replaced today.
I also got a hold of the bulletin about this issue:
-kg
I guess at least the rocker arm did not break completely and break the valve spring and drop the valve into the engine and break the engine...
I really love my silver Z06, but this is very depressing...
I am planning to keep this car a long time and was going to extend my warranty before the base waranty is up (3y/36K?), but now I do not know...
Kristoffer
Edit: BTW, this car has not been abused... I have always been living by the no WOT or over 3500 rpm until oil temp over 150F, and have only done one autox after the break in period and no track time... and the car is completely stock (no tune or other mods)...
Update 3/31/08:
One intake rocker arm broken on each side, on the rear most cylinders, #7 and #8.
BTW, in the pictures the broken ones are just loosely placed back on engine.
Update 4/2/08:
The dealer has received the 2 rocker arms and they are being replaced today.
I also got a hold of the bulletin about this issue:
Document ID: 2007847
--------------------------------------------------------------------------------
#PIP4156A: Possible Broken Rocker Arm On LS7 Engine - keywords cam camshaft DTC engine misfire miss noise push pushrod rattle SES tick valve Z06 - (Aug 29, 2007)
Subject: Possible Broken Rocker Arm On LS7 Engine
Models: 2007 Chevrolet Corvette Equipped with the 7.0L LS7 engine
--------------------------------------------------------------------------------
This PI was superseded to update Recommendation/Instructions. Please discard PIP4156.
--------------------------------------------------------------------------------
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
The customer concern may be an upper engine tick noise, or needle bearings found in the oil pan during an oil change.
Recommendation/Instructions:
If a dealer encounters an engine tick noise, or rocker arm needle bearings were found during an oil change, inspect all the rocker arms. If a damaged rocker arm is found, replace only the broken arm. Replacing the whole set of rocker arms is not necessary.
During the repair the technician may be trying to retrieve all of the needle bearings that were lost. Needle bearings may be found in cylinder head oil drains or oil pan. Clean the drains to retrieve the needle bearings, and replace only the damaged rocker arm.
Notie: The diameter of the needle bearing is larger then the oil pump pickup screen mesh. A needle bearing cannot be pulled into the oil pump.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
--------------------------------------------------------------------------------
#PIP4156A: Possible Broken Rocker Arm On LS7 Engine - keywords cam camshaft DTC engine misfire miss noise push pushrod rattle SES tick valve Z06 - (Aug 29, 2007)
Subject: Possible Broken Rocker Arm On LS7 Engine
Models: 2007 Chevrolet Corvette Equipped with the 7.0L LS7 engine
--------------------------------------------------------------------------------
This PI was superseded to update Recommendation/Instructions. Please discard PIP4156.
--------------------------------------------------------------------------------
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
The customer concern may be an upper engine tick noise, or needle bearings found in the oil pan during an oil change.
Recommendation/Instructions:
If a dealer encounters an engine tick noise, or rocker arm needle bearings were found during an oil change, inspect all the rocker arms. If a damaged rocker arm is found, replace only the broken arm. Replacing the whole set of rocker arms is not necessary.
During the repair the technician may be trying to retrieve all of the needle bearings that were lost. Needle bearings may be found in cylinder head oil drains or oil pan. Clean the drains to retrieve the needle bearings, and replace only the damaged rocker arm.
Notie: The diameter of the needle bearing is larger then the oil pump pickup screen mesh. A needle bearing cannot be pulled into the oil pump.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
Last edited by KGjevre; 04-04-2008 at 03:03 PM.
03-28-2008, 08:12 PM
#5
Drifting
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St. Jude Donor '08-'09
Sorry to hear it. 
Its good you caught it before problems might have happened.
Your car is an '07, you have a 5 year 100K mile warranty.
Good luck with the fix.
augydog
Its good you caught it before problems might have happened.
Your car is an '07, you have a 5 year 100K mile warranty.
Good luck with the fix.
augydog
03-28-2008, 08:18 PM
#7
Racer
Thread Starter
03-28-2008, 08:20 PM
#8
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St. Jude Donor '08-'09
03-28-2008, 08:39 PM
#11
Drifting
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It can always be worst my man, you could have been 1500 miles from home and it decided to let "totally" go. It will be fixed BETTER than new. Hang in there, you z06 guys have awesome cars and I envy all of you.someday for me 
03-28-2008, 08:47 PM
#12
Racer
Thread Starter
It is not like I have not used the revs, but I do not think I have ever hit the rev limiter - so who knows when it happened - it was running fine with no strange noise from the engine.
The only reason I took it in was because the "Service Charging System" message displayed at least a handful of times, starting about an hour into the return drive on a 3 hour roundtrip I did recently, and I was just cruising at freeway speed with normal SoCal spring weather when the charging message started to display.
So I figured that I might as well have the oil changed since I was taking it in, and this was discovered. This was the first oil change. I think the oil monitoring system were at 20% or so left until recommended oil change.
-kg
The only reason I took it in was because the "Service Charging System" message displayed at least a handful of times, starting about an hour into the return drive on a 3 hour roundtrip I did recently, and I was just cruising at freeway speed with normal SoCal spring weather when the charging message started to display.
So I figured that I might as well have the oil changed since I was taking it in, and this was discovered. This was the first oil change. I think the oil monitoring system were at 20% or so left until recommended oil change.
-kg
Last edited by KGjevre; 03-28-2008 at 08:52 PM.
03-28-2008, 08:59 PM
#13
Pro
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Buy a 2008, they fixed the rocker bearing problem. GM stopped using the magnetic drain plugs so no more needle bearing issues being discovered. You don't think the tech is gonna drain the oil thru a screen to find them do you.
03-28-2008, 09:05 PM
#14
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St. Jude Donor '08-'09
03-28-2008, 09:19 PM
#15
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It is not like I have not used the revs, but I do not think I have ever hit the rev limiter - so who knows when it happened - it was running fine with no strange noise from the engine.
The only reason I took it in was because the "Service Charging System" message displayed at least a handful of times, starting about an hour into the return drive on a 3 hour roundtrip I did recently, and I was just cruising at freeway speed with normal SoCal spring weather when the charging message started to display.
So I figured that I might as well have the oil changed since I was taking it in, and this was discovered. This was the first oil change. I think the oil monitoring system were at 20% or so left until recommended oil change.
-kg
The only reason I took it in was because the "Service Charging System" message displayed at least a handful of times, starting about an hour into the return drive on a 3 hour roundtrip I did recently, and I was just cruising at freeway speed with normal SoCal spring weather when the charging message started to display.
So I figured that I might as well have the oil changed since I was taking it in, and this was discovered. This was the first oil change. I think the oil monitoring system were at 20% or so left until recommended oil change.
-kg
03-28-2008, 09:27 PM
#18
Racer
Thread Starter
3797 miles - 20% is ballbark as I do not recall for sure.
03-28-2008, 09:32 PM
#19
Advanced
Who built your engine? I am interested and wonder if this problem points to one particular builder because if the keepers are not set right the spring will dance and can cause the problems that have been seen.
thanks
thanks
03-28-2008, 09:41 PM
#20
Racer
Thread Starter