Customer C8 Z06 engine issue
12-25-2022, 04:26 PM
#61
Le Mans Master
Member Since: Oct 2005
Location: Metro Detroit Michigan
Posts: 7,078
Received 1,817 Likes
on
1,085 Posts
A truly "spun" bearing makes a terrible racket because the crank journals are now hitting the ID of the main bore or the big end of the rod. Spun bearing means LITERALLY that: the bearing has grabbed the journal and literally "spun" in its housing. Most of the time that doesn't happen.
And to me, this engine is making "a terrible racket".
A bent rod is a completely different event and only happens from overloading the engine at low rpm (excess boost at say 2500 rpm) or something in the chamber that prevents the piston/rod assembly from completing its rotation--there by bending or even breaking the rod..
Blue smoke is from a compromised oil ring and/or valve guide issue. It can happen from a cracked piston from physical contact (valve float which caused piston/valve contact) A pinched ring land from too many detonation events and/or overheating which prevents the second compression ring (which functions as an oul SCRAPER) from doing its job, or pre-ignition which is different than detonation and often FAR MORE destructive.
12-25-2022, 07:38 PM
#63
Race Director
Member Since: Jul 2007
Location: Texas Hill Country
Posts: 10,763
Received 2,379 Likes
on
1,238 Posts
12-25-2022, 11:48 PM
#64
Really nasty noises on warranty. Might temp one to hold foot down until noises stopped guaranteeing a new motor not a fix.
12-26-2022, 01:03 AM
#66
Le Mans Master
Member Since: Jul 2007
Location: Arkansas
Posts: 5,032
Received 1,374 Likes
on
793 Posts
St. Jude Donor '09-'10-'11-'12-'13-'14-'15-'16-'17,'22-'23
That is true with any engine, the higher the revs and the colder the temps, the worse it is. IMO, it's never advisable until the oil has got some heat in it.
The following users liked this post:
LukeyW (12-26-2022)
12-26-2022, 04:00 AM
#67
16 Vettes and counting…..
12-26-2022, 06:26 AM
#68
Le Mans Master
Member Since: Oct 2005
Location: Metro Detroit Michigan
Posts: 7,078
Received 1,817 Likes
on
1,085 Posts
Another thing is that valve springs can be more brittle at cold temperatures.
12-26-2022, 09:11 AM
#69
when I picked up my c7z the salesman and I took a short test drive. When we got off the lot the oil and engine temps were under 100 and the salesman told me to “stomp on it and see what she can do”. I just cringed. Ppl do all kinds of stupid with things that aren’t theirs.
The following 2 users liked this post by HMDS:
Michael A (12-28-2022),
Sethbaja23 (01-03-2023)
12-26-2022, 09:22 AM
#70
Race Director
Member Since: Nov 2017
Location: Prosper TX/Austin TX
Posts: 10,961
Received 8,876 Likes
on
4,276 Posts
2020 C6 of the Year Winner - Modified
I've had an engine replaced by GM under warranty only after the State Attorney became involved. I had a second on its way out and sold the car before dealing with the same nonsense again.
12-26-2022, 10:15 AM
#71
If the engine is designed with the right tolerances and has the right oiling system, there is no way it should blow like this in 52 miles. But then we need to stop assuming someone cold revved the engine. it could be an assembly issue or a parts issue.
12-26-2022, 10:58 AM
#72
Burning Brakes
How many miles between failures? Reason for failures?
With full warranty granted on two separate occasions, is this an indication of a weakness in the LT2 - IRT track usage?
12-26-2022, 11:18 AM
#73
Safety Car
Member Since: Sep 2004
Location: Western Chicago Suburbs
Posts: 4,304
Received 5,331 Likes
on
1,985 Posts
I’ve always preferred a 3rd MY Z06 (and that looks like what I’ll end up with). If there are actual issues, hopefully they are addressed by then. At the very least we should all know what we are getting ourselves into by that point. For those of us who plan to keep this car for the long haul, this is more of a concern than those who are ok with relying on the warrantee and don’t plan to keep the car long term.
12-26-2022, 01:18 PM
#74
Le Mans Master
GM will simply replace the engine and we'll never find out what part failed. Hopefully, the oil cooler and lines did not get contaminated causing his second engine to fail as well.
12-26-2022, 02:46 PM
#75
Safety Car
Member Since: Sep 2004
Location: Western Chicago Suburbs
Posts: 4,304
Received 5,331 Likes
on
1,985 Posts
If Mike Ward built the engine this would have never happened 
12-26-2022, 04:33 PM
#78
Safety Car
Member Since: Sep 2004
Location: Western Chicago Suburbs
Posts: 4,304
Received 5,331 Likes
on
1,985 Posts
The following users liked this post:
Jridden (12-28-2022)
12-26-2022, 04:35 PM
#79
Race Director
Member Since: Nov 2017
Location: Prosper TX/Austin TX
Posts: 10,961
Received 8,876 Likes
on
4,276 Posts
2020 C6 of the Year Winner - Modified
12-28-2022, 02:30 PM
#80
Team Owner
Member Since: Jul 2004
Location: Redondo Beach, California
Posts: 39,570
Received 549 Likes
on
376 Posts
The engine builder's name is on a plaque on the engine. Wonder what the guy that built the engine has to say? Yep, in the future, maybe the name of the engine builder will be a factor in the resale price of the car.