Blown LS7 - Need advice *long post*
Back in December, I noticed a loud ticking sound coming from the engine in my 08 Z06 with 75k miles. I decided to play it safe and took it in for inspection at a local chevy dealer (not my first choice but my dad has serviced many vehicles there). At that time they thought it might have had something to do with one of the head gaskets but I kept thinking it had something to do with the valve guides. I expressed my concerns to the service manager who put me in contact with the lead mechanic who assured me that their original repair estimate would include a fix for this. As I was trying to describe the exact issue to the mechanic, he stopped me and said he knew exactly what I was referring to and would take care of it. Fast forward about 3 weeks later and my car is returned with a $5k invoice. The invoice included some parts, labor and subcontracted work to a machine shop for the heads. I know this is probably more than what I would have paid by going straight to AHP but I figured as long as it's fixed, I'm happy to have caught it before any real damage could occur.
Here's what the car sounded like the night I noticed it sounded strange. After finally getting the car back, the ticking sound seemed to have went away and I thought everything was fine. Then last Sunday (2/4/18), I'm driving down the 91 eastbound on my way home and I hear clunking coming from the engine. I look down and see "service traction system", check engine lights, no power brakes, etc. At this point I cruise to the shoulder and wait for a tow truck. https://cimg9.ibsrv.net/gimg/www.cor...e57d7d0747.jpg https://cimg0.ibsrv.net/gimg/www.cor...8f43898310.jpg https://cimg1.ibsrv.net/gimg/www.cor...9280e5fd6a.jpg The car was towed back to Mountain View Chevrolet and I waited for the results. By Thursday, they were able to confirm that it was an issue with the valve guide but also said that I have cylinder wall damage. I was asked to come in this morning (2/10/18) to have a look. Here are some pictures taken of the heads/cylinders. https://cimg7.ibsrv.net/gimg/www.cor...c46ac9993e.jpg https://cimg8.ibsrv.net/gimg/www.cor...d5112eae2c.jpg https://cimg9.ibsrv.net/gimg/www.cor...252602b1b7.jpg https://cimg0.ibsrv.net/gimg/www.cor...d62ee4a37b.jpg https://cimg1.ibsrv.net/gimg/www.cor...8fc8e8ac83.jpg https://cimg2.ibsrv.net/gimg/www.cor...266aea9189.jpg https://cimg3.ibsrv.net/gimg/www.cor...aef80fd2b1.jpg https://cimg4.ibsrv.net/gimg/www.cor...2df3df2e4a.jpg https://cimg5.ibsrv.net/gimg/www.cor...cf510cbefe.jpg https://cimg6.ibsrv.net/gimg/www.cor...18aca2101b.jpg https://cimg7.ibsrv.net/gimg/www.cor...7a08b9f956.jpg https://cimg8.ibsrv.net/gimg/www.cor...7eb6e24e41.jpg The dealer is saying that the valve guide was an issue but is not what led to the blown engine. The blue flashlight in the pictures belongs to the service manager who is pointing out the liquid in the cylinder being the cause of the damage. I should state now this is all foreign to me (I love cars but don't know the first thing about fixing an engine). I am being told that I need a new engine and was quoted at $17k with a credit for the $5k I already paid. I figured here is a better place than any to get more opinions. |
I'd call ahp straight up. Not for dealer or warranty work but if you're gonna pay for it, have the best do it. I would separately try and get at at least some of the $5k back. |
Originally Posted by Jfryjfry
(Post 1596564657)
I'd call ahp straight up. Not for dealer or warranty work but if you're gonna pay for it, have the best do it. I would separately try and get at at least some of the $5k back. |
Looks like the rocker pulverized a Ti intake valve into the cylinder. It also looks like the lassh caps are missing on all the intake valves. They've all been pulverized. Straight up incompetence...dealer owes you a motor. Cut and dry.
|
Originally Posted by z06brah
(Post 1596564683)
I was talking with Kohle last week about getting the heads fixed so I will be calling on Monday to get his advice too. Am I crazy to spend $17k on another LS7? Are new engines sold by GM still prone to the same heads/valve guide problems found in earlier models?
|
Originally Posted by MTPZ06
(Post 1596565744)
Yes, they are...but your failure was incompetence. The mechanic didn't reinstall the lash caps on your Ti intakes.
Seriously, thank you for your help. |
Originally Posted by z06brah
(Post 1596565802)
Is there any way to prove this? Probably a dumb question, but can you point out which picture(s) you're able to spot this? I will definitely bring this up next week when I talk to the dealer.
Seriously, thank you for your help. |
How many miles have you put on the car since picking it up? Probably a thousand or less?
|
Originally Posted by MTPZ06
(Post 1596565701)
Looks like the rocker pulverized a Ti intake valve into the cylinder. It also looks like the lassh caps are missing on all the intake valves. They've all been pulverized. Straight up incompetence...dealer owes you a motor. Cut and dry.
Show those pictures to 6 different cylinder head shops and all 6 will tell you the same thing. In fact I recommend you do just that. Get a statement from multiple head experts and present all of them to the dealer. Incompetence during assembly, “missing lash caps” on the titanium intake valves caused the valve failures, and one valve dropped destroying the engine. Everything in the motor is now suspect. Block, crank, rods, cam, lifters etc. Don’t settle for a rebuild, dealer owes you a new motor installed with no out of pocket expense to you. You can also contact Tony at https://www.mamomotorsports.com/ as an expert. |
Smoking gun....
|
Originally Posted by MTPZ06
(Post 1596565837)
How many miles have you put on the car since picking it up? Probably a thousand or less?
I picked it up and drove it down to Irvine (about 45 miles one way) for work the week of the 28th (my commute to work is only 2 miles one way) and back to Rancho Cucamonga that Friday (2/2/18). Driving back to Irvine on 2/4/18 is when the engine gave at about the halfway point. |
Originally Posted by Rookieracer
(Post 1596565889)
:iagree:
Show those pictures to 6 different cylinder head shops and all 6 will tell you the same thing. In fact I recommend you do just that. Get a statement from multiple head experts and present all of them to the dealer. Incompetence during assembly, “missing lash caps” on the titanium intake valves caused the valve failures, and one valve dropped destroying the engine. Everything in the motor is now suspect. Block, crank, rods, cam, lifters etc. Don’t settle for a rebuild, dealer owes you a new motor installed with no out of pocket expense to you. You can also contact Tony at https://www.mamomotorsports.com/ as an expert. Thank you again! |
The destructive fluid in the cylinder could possibly (probably?) be nothing more than coolant that inevitably gets everywhere when you pull a head. |
Another thing the dealer pointed out was that the cylinders were no longer honed which caused oil to leak into the cylinders. They're acknowledging that the machine shop improperly repaired the heads but insist that the engine failure was due to this cylinder honing problem. I just can't see how these two things would be unrelated
|
Originally Posted by Jfryjfry
(Post 1596565966)
The destructive fluid in the cylinder could possibly (probably?) be nothing more than coolant that inevitably gets everywhere when you pull a head. |
It is obvious from the pictures that they did not put the lash caps on, which destroyed the motor. They owe you a new motor.
Yes new motors have same issues, and possibly the rod issue as well. |
Were these supposed to be stock heads?
The springs are dual not beehive OEM did they tell you that OEM parts were not being supplied? :cheers: DH |
Originally Posted by Dirty Howie
(Post 1596566577)
Were these supposed to be stock heads?
The springs are dual not beehive OEM did they tell you that OEM parts were not being supplied? :cheers: DH Edit: Then again, I'm not sure if the machine shop they used included these dual springs as part of their "fix". I believe the vehicle was 100% stock when I bought it and I had never modified anything. |
Even if the motor had no oil and wore the cross hatching off, the result would not be what happened. A seized motor, spun bearing(s), broken rings maybe. But not the broken valve which is, iirc, what likely scored the wall. I will say that it is odd that there is no crosshatching left (If that's even true) but again, that isn't why the motor failed. And nd even if it was a problem, it could have ran for years like that. But it obviously won't run for years (or even 300 miles) without the caps. |
100% due to no lash caps installed. Do not accept their ridiculous reason.
|
All times are GMT -4. The time now is 01:27 AM. |
© 2024 MH Sub I, LLC dba Internet Brands