I do not understand why GM is not responsible for this huge problem! They designed the engine and picked the vendors to supply the correct parts! Now we are supposed to spend thousands of dollars MORE to correct their screw up!

@browningbelgium2326

5 ай бұрын

I went aftermarket with Lingenfelter immediately after buying mine because of this ticking time bomb. You're right, GM sat on their @$$ and didn't do a thing.

thanks for the vid. the wiggle test after the springs were removed shows that the valve guide clearance was out of spec but your measurement method measuring valves still under spring tension and measuring at the top of the stem and not in line with the rocker arm arc along with not measuring normal to the valve stem will give you wildly inaccurate measurements. that being said, the guides were out of spec and you did the right thing by replacing them. thumbs up.

Test Oil Contamination every 5-10K miles. I found titanium at 22,000 miles in my 07 Z06 Ron Fellows, and at 25,000 it had increased a lot, so we pulled the heads for inspection. I had to agree to pay if nothing was wrong but I knew. Pulled the springs, Exhaust valves literally fell out of the heads so loose. $7,000 later GM paid for New heads, New Exhaust valves and gaskets and labor. I had to pay to pull the pan and remove rocker bearings from the oil pickup, GM said that was not warranty covered. Get your Z06 Oil Tested PLEASE!

@Godsblessings1111

5 жыл бұрын

Where do you send your oil for the test? Thank you

@JosiasRivera

4 жыл бұрын

ZL1 / 4 Play google oil spectroanalysis labs.

@RevolutionMuscle

4 жыл бұрын

@@JosiasRivera Oil isnt the problem. Its defective valves. Its likely GM replaced your valves witht he same defective units that failed on your car. I know this post is old but if you still have the car you might want to check them again.

@JosiasRivera

4 жыл бұрын

TheHardcoreLife I’m not saying oil is the problem. I’m just responding back to his question.

@milojanis4901

4 жыл бұрын

What were rocker bearings doing in the oil pump pickup? Did they fail, also? I have an LS7 in a C5, and though the wiggle test has largely been discounted as inaccurate, the valves shouldn't wiggle at all if there's no problems. If they wiggle at 20,000 miles, there's a problem. I TOTALLY agree with the post that says GM may have reinstalled the problem. SOME, not all, but some of the Ti valves have a rough finish. GM bean counters decided to skip a process called "tumble polishing". Another HUGE problem, and main reason the intake and exhaust valves wear out the guides, is the valve guides are NOT CONCENTRIC to the valve seats. This causes the valve to "bind" somewhat in the guide as the spring seats the valve. I had my heads done when the engine was built by a well known engine builder in Wixom, Michigan. I would've thought he made certain the seat to guide was spot on. But you would also expect.that for $15,000.00, I would've gotten titanium valvespring retainers, which I did NOT get. At 22,000 miles, my guides are also worn out, intake and exhaust. If you want them redone at a quality place, try American Heritage Performance in California. That's where mine are going.......

Finally, out of all the other video’s I’ve watched on this topic, you explain right up front specifically what causing the problem. Many others simply bitch about the issue and state that it needs to be fixed, while never explainn the cause.

Hey John, Saw your new video on the assembly of your ls7 heads and the video looks great. Hope you are doing well also and glad you are back with a video update!

Best vid on dropping valves/replacing valves on KZread for c6z's 👍👍👍

Nice video! Cool time lapse and shop tour

I have a new respect for TSP after watching this. That machine shop is fucking legit.

Thank you for not adding music👍👍👍👍👍👍👍👍👍you don’t check the clearance that way. Take springs off remove seals clean oil off then you can check.

Thanks for the video. I'm doing this starting tomorrow.

Excellent information Thanks

Awesome video. Yes, some of it may be a good advertisement for Texas Speed, but so be it. I've been around this stuff a long time. I was a Tool & Diemaker for 40+ years. If I do say so myself, I am very impressed with Texas Speed. I knew they did good work, but didn't know they ground their own cams. I see cam grinder is a Landis. I ran a Landis O.D. grinder for almost 20 years that accepted pieces up to 8 feet long. They were based in Pa. at one time. Don't know where they are now, maybe still Pa.? Anyway, I see Haas machinery also. All really good equipment. Looks like you went to the right place. These LS7s are great motors, but ticking time bombs until heads are redone.....

Gm has a history of not righting wrongs and this is no different. They should've recalled these values guides under warranty.

Nice video. Texas speed doesn't look like they're playing any games...

Jason built my Ls7 as well !

I just had sent 69k mile 2005 Corvette LS2 heads to Katech for porting, and they called and said 11 of the valve guides are worn beyond acceptable tolerance.

Great video man. I am sorry, but I played the Benny Hill theme on the quiet parts of the engine tear down. lol

John, nice presentation. A couple of thoughts. First, do you have a "slow-mo" version of the head removal. It was difficult to pause the video fast enough to see what you were doing, so definitely slow motion would be great. Second, having watched several head jobs that check the guides, I noticed you measured at the top of the stem and not at the guide itself. I'm really not sure who is right about this. Where did you get your information to test the distance at the top of the stem and not at the guide. Thanks John for the video!

Your the only person I’ve seen has a z07 velocity yellow corvette. I would love to see a full video on the z06 in detail

This breaks my heart. I didn't even realize early model C6 Zr1's had this issue. Thats my dream car. The hell with a C7Z.

Any word on the newer 2018 and 2019 z06/z07 any overheating issues at track?

I have a 09 c6z. Bought it with 32k miles now have 53k on it. I don't know if the previous owner checked on this issue but so far I'm good. I do have a warranty for another 2.5 years and plan on keeping this car at least that long. What do you recommend I do?

Damn there must be 10 million dollars in CNC equipment in that building.

@Nobody-dc8dp

Жыл бұрын

Haas is trash

What electric ratchet are you using? Would you suggest buying one? 0.009 in with the valve spring installed?!!! wow...

Does Texas speed give you any guarantee that if your engine blows in the same manner with these new valve guides

Loved my ls2 7k rpm tbss that is

ZR1 had the LS9 and didn't have the valve guide issues, only LS7 in the Z06, shitty luck that happened to him though

Did you also measure 90 deg from the one shown in video? I would think that tangent in line with the rocker shaft would show more wear since maybe the rocker is pushing out slightly (towards outside of car) while also pushing down. (The direction shown at 10:15)

@Mike44460

3 жыл бұрын

I agree one hundred percent. Looking at the wear pattern on my rockers it was obvious that there is side loading on the valve stem. I solved that issue with Crower Shaft Rockers, big bucks for a street car, but big peace of mind.

GM tried to save too much money again.

He says he has ZO7 optioned ZO6. Is that an even more special ZO6 that is rare, or are all ZO6 made that way? I want a ZO6 within the next 12 months and want to know what to look for. Thank you to anyone who can answer my question.

So even fully built this zo6 is still going to have valve issues ?

2022 update in the future? Still have the 13?

Hi bud, does the LS7 engine require lash caps and if so on which rocker do you install the lash caps on? All the rockers or just the intake side or exhaust side?????

@ssoffshore5111

2 жыл бұрын

Intakes, over the Ti valves.

Did you say at the start of the video that the person who dropped a valve was a c6 zr1 ? I thought it was a zo6 issue ?

can you tell me what is the Katech part number for the exhaust valve upgrade kit that you used I am replacing the engine on my 2008 z-06 that an exhaust valve parted on the number 4 cylinder with 60000 miles and am installing a new set of GM-LS7 heads and would like to fix this exhaust valve problem so that it will not happen again. I received my new LS-7 block from Texas speed and performance and am in the process of installing the new set of GM factory LS-7 heads. would like to know the results of this exhaust valve and valve guide upgrade went on your engine.

@johne4557

7 жыл бұрын

I used pn# SKU: KAT-6586 Titanium valves from Katech, Texas speed did all the machine work and installed Bronze guides

what is the cost to have this problem fixed. deserve 5 🌟. thanks

hi awesome video .Ive wanted a wing like that for my z06 but didn't know they made it for the c6 .can you tell me how you got it?

@johne4557

7 жыл бұрын

Its specially designed for C6 but uses actual C7 Z06 stage 3 Aero wickers. I purchased it from www.innovativeautocreations.com/shop

@rogelio7524

6 жыл бұрын

John E thanks you so much

is that rear spoiler the same exact one that comes on the C7 Z06?

@johne4557

7 жыл бұрын

Its specially designed for C6 but uses actual C7 Z06 stage 3 Aero wickers. I purchased it from www.innovativeautocreations.com/shop

Can you tell me where to get a rear spoiler like the one on this car?

@johne4557

7 жыл бұрын

purchased online from www.innovativeautocreations.com

Hey Dennis how did you get GM to pay? I also have a 2007 ZO6 with 28,500 (never raced) and at recent oil change found a rocker needle bearing on the magnet of drain plug! SO , I need to do the preventative rocker bearing replacements and exhaust vale change out too , however , when I called GM warranty they would NOT pay anything because car is 12 years old regardless of LOW mileage!!!

@kingbrutusxxvi

5 жыл бұрын

Lee - Sorry to chime in, but my cousin was the QC Director at the plant from the end of the C5 through the second year of the C7 (when he retired). I bought a low mileage (8,500 miles) 2010 Z06 in 2016 because I missed having a 427-powered car and talked to him about the LS7 valve issue and he said, to the best of his knowledge, GM had never paid for the fix because they didn't consider it a "recall-worthy problem". According to GM only 1,200 total sets of heads (made by an outside vendor) were ever affected and that was too small a number to issue a recall. I've read several posts on forums (though far from a lot) where people claimed GM paid to fix the problem but I've never found anyone at GM to corroborate that claim. Trust me, you're not alone in your frustration. Cheers.

@leepritchard6453

5 жыл бұрын

@@kingbrutusxxvi Thanks so much for taking the time to respond. I was on the phone with 3 different GM warranty people for over an hour the other day and it was an exercise in FUTILITY!!! Go figure...I'll be doing the rocker arm bearing repair and heads (exhaust valves etc) next week because I do NOT want to be one of those that drop a valve and have a $20k engine replacement instead I'll take the $4k repair Blessings Psalm 143:8 Revised Standard Version (RSV) 8 Let me hear in the morning of thy steadfast love, for in thee I put my trust. Teach me the way I should go, for to thee I lift up my soul. Narrlee

I’m really thinking about buying a c6z 2008-2013. I’m not an expert on motors, can anyone tell me what all exactly I need to buy to replace in the engine to prevent a valve from dropping. Also what’s the price estimate on how much it’ll be to upgrade everything?

So zr1s also have this issue?

I've been looking at used Z06 Vettes from 2009 / 2010 and this might have scared me away... I'll admit I'm not a engine guru, so a question for all follows: If I purchase a Z06, I'm assuming that if a head is damaged, the car don't turn on, or will at least have a knocking sound right? Also, how expensive is the Valve replacement (to include labor) on average. Thanks!

@MasterCarguy44-pk2dq

6 жыл бұрын

Only a very, very small percentage of LS7's had issues. I'd not worry about it. Besides, once you start moding, your powertrain warranty is gone at that point anyway. Especially if you put a tune on. Moss-Magnuson Warrany Act only applies to stock cars. And aftermarket tuning of a vehicle is a violation of federal law.

@RodneyThomas

6 жыл бұрын

MH motorVlogs thank you!

@RodneyThomas

5 жыл бұрын

365 AutoDrive thanks brother. I REALLY want a C7, but I should get my feet wet with an earlier model. I really cannot wait to join the club!

Where did u learn to do this?

heard it only happens to a very small percentage, should one get it replaced or just keep driving. and any symptoms /problem that it exhibits?

what was the total cost to do this

You said you had nine to ten thousands on the intake exhaust but you never or I didn't catch, what the measurement was supposed to be. also, even with that side play I don't understand why the retainer didn't hold the valve in place...? In order for the valve to drop either have to break it or the retainer has to come loose. Which is happening?

@ssoffshore5111

2 жыл бұрын

The valve head snaps off, typically on the hollow stem exhaust valve.

I have similarity issues with my C6

I recently purchased a 2006 Z06 LS7 with 47k miles. I have done some research on the 'dropped valve' issue. Supposedly, the 2006 model year was OK and preceded the wrongly manufactured valve guide issue. It has not been serviced for that problem, has 47+k miles and runs perfectly with no valve noise. Can anyone tell me if there is something to be concerned about? Thanks in advance.

@YELLOW08Z06

7 жыл бұрын

Get them replaced period

@johne4557

7 жыл бұрын

l.facebook.com/l.php?u=http%3A%2F%2Fread.uberflip.com%2Fi%2F834132-july-17%2F77&h=ATOPqJlypbNelpNkNrOBAkM7GtHwxYZs_1jR8pUXE-VqJg0AnIE17KRhtLRY-aKj0KRJbtArU6-ILJNOQzlHjYFIhfK_7QMB8FqUamXqpH-s5P2p1R8sXsO3g9M&s=1 here is a good read its a downloadable pdf go to page 78

What is the name of your shop ??

you still uploading?

Great video but I'm Not gonna lie , never thought I'd see a 7.0 liter LS7 Vette owner who is wearing a Tesla jacket. What's next you're going to tell your car doesn't have any cats? ;)

You are fixing a year that didn't have the problem. You range js acceptable and you did t measure properly. Should have had the springs removed. But hell, nothing wrong with a nice ahead job.

@ssoffshore5111

2 жыл бұрын

EVERY year LS7 has had the failure. Don't buy into GM's CYA FUD! I'm yet to see a stock LS7 that didn't have some moderate level of valve play. FWIW, I've also seen it on some "fixed" heads as well, but to a far lesser extent.

LS engines are nice, but costly! I guess that's why I'm still using a big block Chevy. 🤣

How did you pull the heads without going under the car and remove the headers? I'm about to pull my heads to have them fixed and want to do the job without the extra work of the headers.

@johne4557

5 жыл бұрын

Randy I did go under the car to loosen the headers at the pipes completely so I could access rear head bolts. If you can a least pull one of the headers out far enough it makes it easier. Hope this helps and good luck

good video, are you going to do a follow up vid installing the heads?

@johne4557

7 жыл бұрын

Yes i'm working on it right now

@bjmsamrlm

6 жыл бұрын

Thank you for taking time to make this video and its sequel! Did you "wiggle test" the reworked heads? I am curious to know how significant the difference is when measured with a dial indicator.

Hey I subscribed, I'd like to get in touch with you because I lOVE the 2013 Z06/Z07 but I'm thinking about a 2011 inferno orange Z, pretty sure it has valve work too, $44,900. Anyway, private message me if you want to talk corvettes

@ZorawarSohi

6 жыл бұрын

Z3rhairstylers Fuch

On his ZR1 ??

So what has to be done to keep even a stock ls7 reliable?

@johne4557

5 жыл бұрын

FX have reputable shop rebuild your cylinder heads with new guides and replace the rocker arm needle bearings with the Comp Cams trunnion sealed bearing upgrade

@RK1FX

5 жыл бұрын

@@johne4557 after that will it be reliable? I dont beat on mt cars much.

Don’t buy replacement GM heads. If you have a reputable competent aftermarket specialist like Lingenfelter rebuild your heads with superior aftermarket parts the issue won’t come back.

What will cause a valve to drop?

@litonica2002

2 жыл бұрын

It’s just an issue with these cars because GM put hollow valve stems and I’m not sure what else people replace to fix it but replace the head completely and go with a heads cam package for more power and reliability I’m looking into getting a C6Z and I’m tryna see what people do to fix it beside the heads since that’s $3.5-5K

Pretty sure the problem wasn’t even present on any of the engines produced after 2011 anyway.

@ssoffshore5111

5 жыл бұрын

Steve Hartsock false

I thought the valve guides were the issue, not the actually valve?

@johne4557

5 жыл бұрын

Correct the guides are not machined in the center of the head correctly, I just upgraded to titanium valves

@bailey9r

4 жыл бұрын

Yes guides are the issue in that they centered so they wear the valve stem till it breaks off. A hardened valve head will not compress like gasses so it causes major damage to block and head.

What's more expensive, an extended warranty or this?

@bsfunk44

4 жыл бұрын

I just bought a 21k mile 2010 z06. I got a 5yr 60k powertrain warranty for about $2k. Third party.

@bsfunk44

4 жыл бұрын

But I'm going to have the heads fixed anyway.

@ntme9

4 жыл бұрын

@@bsfunk44 Right on! Thanks

@jackwebb7833

4 жыл бұрын

BSfunk44 what third company did you use?

So 2013 ls7 had the same problem? thought they said only effect 08-11 ls7's

@01lowbird

5 жыл бұрын

every 7.0 no matter the year or vehicle is susceptible to this

@milojanis4901

4 жыл бұрын

Exactly. There are maybe 1 or 2 out of 10 that MAY be OK. If you continue to run one without checking the valvetrain, it's kinda like the old Fram filter man commercials; "You can pay me now (less $$) or pay me later" (lots of $$).

There should have been a class action lawsuit against GM for this failure. There isn't any reason the customer should have to pick up the bill on this!

Must be pretty embarrassing putting your name on it and that’s gonna blow

are you a tesla mechanic?

@johne4557

5 жыл бұрын

I do work on tesla's but not exclusively I work at an independent shop we work primarily on American and Asian imports . I am an ASE Master Technician technician also Master Hybrid & EV certified . We performed State Safety Inspections for Tesla dealership down the street the manager gave me Tesla jacket for providing our service.

@mobleyMobley

5 жыл бұрын

@@johne4557 cool, great video!

Why Does everyone Keep saying Dropping A Valve? These Valves Are Breaking Or separating , Dropping Involves The Keepers Or Retainers Failing Or Coming Loose And the valve Falling Into the Motor. That Is Not What's happening. The Valve Stem Is breaking. Big Difference, At Least This guy Is saying Why and what. Thank you For That.

@milojanis4901

Жыл бұрын

If the valve drops into the cylinder, the piston and head don't much care HOW it got there. All that matters is that it did. Period.

@guardpass

Жыл бұрын

…because the VALVE DROPS into the cylinder. That’s called “dropping a valve”. Semantics.

@tbree8417

Жыл бұрын

@@guardpass did you not read what I wrote? It's not semantics there is a huge difference. non professionals say "dropped a valve" because they heard it somewhere and it sounds like valve in cylinder , but they don't really know what it means. I explained the difference, you should read it then maybe you would understand it's not semantics.

@clane5599

Жыл бұрын

Probably more like sucked it in and kissed! 🎉.

Well James Knipp, you messed up with them LS7 heads lels

Call up the engine builder and ask why he used crappy valve guides in the first place.

This is why I own an nsx r and not a corvette, Honda would have done a recall if they had this issue in their cars! GM is a terrible and greedy company

U can only read that on one cylinder lol

John, I don't see any mention of a 2010 with 23k miles that dropped a valve on this thread on Corvette Forum. Could you ask him to post so we can add it to the list. www.corvetteforum.com/forums/c6-corvette-zr1-and-z06/3448116-ls9-valve-train-matters-reported-on-the-cf-2.html

Now I see why so many used Corvettes are for sale and they are still trying to get 50 and $60,000 for those used corvettes

i thought the valve guide issue on the LS7 only ranged from 07-11 i thought the 12-13 were not apart of it

@ssoffshore5111

5 жыл бұрын

All LS7 heads from the factory are suspect.

@ssoffshore5111

5 жыл бұрын

I agree the majority will likely go for a long time without issues, but I think it would be foolish for someone without a warranty to just stick their head in the sand and pretend there's no potential problem. As a Z06 owner and engineer, I have done a lot of reading & research on the issue. Not because I'm overly concerned, but more so out of curiosity. I've come to conclude that ANY LS7 with the factory heads should be inspected at regular intervals. Why? Even if only 5% of these cars end up breaking a valve, resulting in major (total?) engine failure, that's still a significant number. Countless (thousands of) heads have been checked and found to be WAY out of spec and been replaced/fixed before complete failure. Had these not been done, what would the real failure rate be? Considering most of these cars see little usage, the number of LS7's with excessive guild wear or complete failure is enough that any owner should be at least casually concerned at the minimum. It's probably very sound advice to have the valve wear checked every so often. Is it a hassle? Yes, but the cost to completely replace an engine to an out of warranty owner is huge! My Z gets driven, it has 57k on it now. I'm probably going to do H/C/I this year not only for the power, but also to not take any further gamble regarding the potential ticking time bomb...

Spinning a 427 to 8k ..... lol

@johne4557

5 жыл бұрын

Yeah that's pretty high but the Ls427 red lines at 7000rpm

Duudde....sweet....duuuuuude....sweeett!!!! Duuudde....coooool....duuude....sweet. awsoooooomeee....sweeeet...coool...sweeeeet...ugh.

I just can’t take anyone with a Tesla jacket on seriously 🤷🏼‍♂️

ZR1's have a LS9. You have a LS7, totally different motor. And based on the number of LS7's made vs the failures, the failures are so small that it's under 4%. There's no need to be swapping/upgrading the heads or anything in these stock.

@rachelleb.2392

5 жыл бұрын

MH motorVlogs 0_o ... terrible advice

@rachelleb.2392

5 жыл бұрын

365 AutoDrive ignorance is bliss for you, right?

@rachelleb.2392

5 жыл бұрын

365 AutoDrive it is blown out of proportion, but my stock, early build c6z blew the motor with what I considered low mileage (30k). Either way, things happen, I just don’t think it can be denied, but your response is a bit more measured in that regard. I think we’re in agreement.

What year was your buddies ZR1?

@johne4557

3 жыл бұрын

2010 ZR1

GL buddy this reason is exactly why Ford is pulling ahead of everyone I hate Ford's to!

Im retired GM service tech. GM cant get the centerline of the seat/guided the same? The valve head breaks off? Junk valves? Worn guides? Are they worn in an oval shape or are the worn round? Im gona get some guff over this...bring it....worn guides are from junk springs...springs where the top and the bottom are not parallel. It has nothing to do with the tip of the roller rocker not being in the center of the valve stem or oem stamped steel rockers...Big block chev has valves that are angled in 2 directions. Have you ever heard anybody say they needed roller rockers to keep the guides from wearing out....i have messed with a couple sets of heads, this set was on a L88 427 i bought....ran it in my boat and it ran fine kzread.info/dash/bejne/Y2WZus5_m73Lm7A.html Nothing more than bad springs.....Easy to prove, get a head with bad guides...put the spring on the valve, put the rocker are on and figure out how to use the pushrod to get the valve off the seat. Good spring, valve will move around with your pinky finger, bad spring and it will be pushed to one side, really bad spring and you will need a tool to move it. Ti exhaust valve raise redline? That aint gona happen, ignition has a rev limiter, the intake valve is bigger/heavier than exhaust, it will be the first to float....and round up a dyno sheet for your motor....see where peak hp is? You need to shist a few hundred rpm past that...or less..short shif is always best

Folks, you can't take all this KZread nonsense serious. There was such a very, very small percentage of LS7's with issues. And that supposed lawsuit never happened. If your going to mod the car, your warranty of gone anyway.

@TheZQQH6

5 жыл бұрын

@365 AutoDrive Really? It's a Z06 they are track ready cars made to beat on. JMO

@clutchcarabelli8054

5 жыл бұрын

Mine is 12 years old engine never opened up and runs better than it did from the factory thanks to Long tubes full exhaust cold air and a tune... I've read plenty of stories with people with 80,000 plus on them... Will they pop? Of course. Are the valves the weak link? Yep... people do the damnedest shit nowadays though not changing their oil for 10,000 miles on a car like this? Nope... I don't care what they say about synthetics mine gets new synthetic every 3000 like clockwork... And this guy putting in solid valves going to rev his car to 8 grand ?... Nope :-)

@mobleyMobley

5 жыл бұрын

@365 AutoDrive www.corvetteblogger.com/2015/10/16/gm-hit-with-class-action-lawsuit-for-defective-c6-corvette-ls7-engines/

This is why Chevy has a bad name. They know it’s a problem but they’ll blame the customer before they take blame. Explains why they went bankrupt.

@stevehrocks

5 жыл бұрын

JIMBO SLICE a problem with less than 5% of motors and solved after 2011 anyway. Still more reliable than Ford or Chrysler.

You shouldn't be putting out videos on technical issues such as clearances you haven't got a clue.

Now I see why so many used Corvettes are for sale and they are still trying to get 50 and $60,000 for those used corvettes