BLACKONBLACKZ06

This is back in November 2001:
Information from Dealer

"Performed vacuum test. Only 8 inched of vacuum
Number 4 cylinder has no compression.
Tech 2 indicates all cylinders misfiring.
All indications at present are engine has been overreved
And valves have floated.
Spoke with district service manager for General Motors.
And General Motors has declined warranty repairs due to
Driver error. November 12, 2001." Unquote.

The dealer told me that tech support said that I down shifted
Causing the RPM to exceed 7300.... floating the valves.
And that is the only scenario that fits...

All I can say guys is...that did not happen...and I don't really like
Being called a liar...

Today and $8,500.00 later guess what was wrong with the engine??
One broken valve spring... :mad

Heads/valves/pistons etc all checkd fine... :mad :mad :mad


[Modified by BLACK/BLACKZ06, 9:57 PM 2/14/2002]

ZO6LS6

Doug, I remember when you had this happen, sounds like you need to seek counsel..........for recovery of "Wrongful Diagnosis", get the original report from the dealer, and the one where the needless repairs were SUPPOSED to be done, and see about recouping you're losse's...........
$8large is too much jack to let slide, not to mention you lost you're warranty also.......... :bs

RPO_Z06

So they still won't pay for it ? :bs Nail em !

BLACKONBLACKZ06

Just got back the full information today...

I will be taking the Pistons/valves and pics to the offending dealer
next week after picking up the Z in Detroit...it should be very interesting to see what the dealer has to say....then GM....then the lawyers.

What really pi$$es me off is that the dealer called me a liar...ya know.
:mad

ZO6LS6

Doug, whatever you do........DO NOT let them have the parts, and do not let them out of you're sight when they are examining them.........
You may never see the originals again...........
:yesnod: :eek:

BLACKONBLACKZ06

Just gave the Dealer copies of the paper work...we talked for awhile about my destroyed engine.... :rolleyes:
I then told him that Katech looked over the complete engine and did he want to know what they found....
Thats when I layed the broken valve spring down on his desk and said...
That is all they found......mercy :crazy:

The dealer is now saying that they didn't call me a liar...GM did.
The dealer didn't deny warrenty...GM did.
He is on my side... :lol:

By the way....the Z is running great.........another 180 miles and out comes the break in oil....in with the good and WOT.....it really is hard not to jump on it :cheers:

SWCDuke

In case this happens again, you really can't "float" the valves with hydraulic lifters. At some point they just collapse and the valves barely open. It's like a rev limiter under power, and probably won't do any real damage even it you overrev on overun by downshifting too early.

Unfortunately you just got an incompetent tech or service department. A broken valve spring is probably just a material defect - it's happens once in a while. They should have been able to diagnose it and replace it in a day, assuming a valve wasn't bent. In that case it shouldn't have taken more than a couple or three days.

A warranty decision by GM is only as good as the diagnositic information they get from the dealer. Garbage in - garbage out. Sue 'em in Small Claims Court, but name both the dealer and GM as co-defendents.

Duke


[Modified by SWCDuke, 9:38 PM 2/28/2002]

BLACKONBLACKZ06

Thanks Duke...
The Dealer said that they would contact GM and get back with me :lol:
It is really unfortunate, This Dealer sells quite a few Corvettes, so I assumed their service department would be a good one.
The Vette salesman is really a great guy...

They told me that floating the valves by down shifting is a very common problem and have repaired many engines with piston and valve damage.

Z06Scott

Did you try to go to your insurance company? My sister recently bent up the braces in her convertible top when she closed it on top of a stereo she had in the trunk and insurance covered it. It sounds like your problem may have been something which should have been covered under your comprehensive coverage given GM claimed driver error. If not definitely get a lawyer! :boxing

forloop

Just in case you have to go to court. Make sure you bring the hour long video you got, telling how to set your Z06 up for racing. I don't recall it ever mentioning that racing would void your warrentee.

I know when I break something that is the first thing I am going to mention.

Good Luck,

Rick

1fastdog

Was this an aftermarket cam in the engine...? If it was what brand springs were used? Stock or aftermarket as well? I think your car had a cam before this happened didn't it?

A missed diagnosis is a drag, who took $8500.00 bucks of your money only to tell ya it's a broken valve spring? Sounds like they weren't a sharp bunch unless you were having mods done anyway..


[Modified by 1fastdog, 9:51 AM 3/1/2002]

SWCDuke

From you original post you indicated the only problem was a broken valve spring, so I take it no evidence of piston/valve contact was found. A broken valve spring might allow the valve to drop enough to contact the piston at TDC, but it might not. If all you had was a broken valve spring, a material defect in that spring is the most likely cause of the failure. Again, "floating valves" usually doesn't occur with hydraulic lifters because the lifter will usually collapse before the valve gets tossed off the lobe profile, but I suppose it is possible with an aggressive hydraulic cam like on the Z06 to toss a valve off the lobe before the lifter collapses.

I recall a thread a few months ago where someone did overrev severely by hitting first on a 2-3 shift of something similar to that. I don't recall that any piston/valve contact or broken springs resulted - just some bent pushrods.

Duke