FuzzyLog1c

iTrader: (4)

During my cam installation, I reused the original valve locks with new springs, seats, seals, and retainers. Upon starting the engine up, I heard a clicking sound that I only just identified. After tearing down the entire valvetrain, I found that one of the two locks on the #8 cylinder intake valve stem were missing, and the other was cracked in half and just barely hanging on.

Obviously, I'm relieved that I caught the problem in the nick of time, but this is my daily driver and none of the shops in my area have replacement locks in stock.

Question #1:

During the diagnosis of the problem, I also found that my #6 cylinder was not providing power by disconnecting and reconnecting the ignition coil attached to the #6 spark plug. Is it possible that the missing valve lock half somehow got into that cylinder or jammed the lifter? There's a lot of space behind the top of the heads that the lock could be hiding in, but short of removing the heads, I won't know.

Question #2:

I've identified that Comp Cams #623-16 is the correct lock for my LS2 application. While I'm at it, do you think it's worthwhile to replace all of the locks in the valvetrain? I think that this might've been an isolated incident due to installer (namely, me) error in setting these locks in the retainer, but maybe this is something that happens with stiffer springs (in this case, Comp 26926 with 470 lbs open seat pressure).

EDIT / Question #3:

Ordered 16 new Comp cams locks. In the meantime, do you think I should be taking off that head to ensure that there's nothing down there? I did a visual inspection with a flashlight--even peered down the pushrod holes--but couldn't spot anything.

01_SuperSlow

iTrader: (7)

Wow.

1. In that case, I don't think the coil problem is related. I think the lock could be in the lifter tray though or maybe down in the oil pan.

2. If I were you I would replace them all or peace of mind.

3. I would look for that damn lock everywhere before firing it up again, you don't want it to reappear at the wrong place one day
and

FuzzyLog1c

iTrader: (4)

Out of curiosity, do you know where it could and could not go? Taking heads off is going to throw a wrench (literally and figuratively) in my schedule.

01_SuperSlow

iTrader: (7)

My guess is lifter tray or oil pan. I don't think it could hang on to anywhere else.
Run a strong magnet underneath the oil pan and see if you can fish it out. If not, stick a pen magnet through the pushrod holes and see how that goes.

FuzzyLog1c

iTrader: (4)

"Lifter tray" was exactly the term that I needed to Google images of the area beyond the holes for the pushrods. Thanks. I'll try to pick up a pen magnet as soon as I can and fish for it.

RADEoN

iTrader: (12)

i mean if it fell into the oil pan, it's not gonna be able to get through the pickup tube screen anyway, but I can't think about how big the valve locks are on these anyway... would it make it through the drain plug?

FuzzyLog1c

iTrader: (4)

Definitely. They're the size of peas.

punishmentcycle

iTrader: (6)

personally i think the lock wasnt all the way seated when u put them in..with that said deff replace them all and find the other lock..even if that means pulling the head. use a pen magnet first and with luck youll find it.. also try sticking the magnet thru the drain plug... do not start the engine till u find this!!..

theres alot of spaces for the lock to hide and most likely its around the lifters..if its bouncing around by the lifters then its a ticking time bomb

FuzzyLog1c

iTrader: (4)

Thanks for your help, guys. The broken valve lock was the source of the ticking issue. I replaced all valve spring locks with Comp Cams 623-16 hardened valve locks. The dead #6 cylinder was due to me over-torquing that spark plug. I replaced that spark plug with a fresh NGK TR5IX (same as the others). The car sounds great, and is due to be re-tuned by Jannetty Racing on Monday. I'll follow up then.

-T-

iTrader: (2)

You should really think twice about getting your tune at this point. Just listen to some reasoning... You changed all valve components with the exception of the valve and valve guides, also you are increasing your valve lift. Take your heads off and take them to a shop, have them do a valve job and check your installation. Seat pressures are important especially with our stock valves.

If you don't have time or money to do it right the first time, then when will you have either to rework after a failure?

FuzzyLog1c

iTrader: (4)

I did it right. Spent over 60 hours on it. I'm not going to have someone pay to check my work when I checked and rechecked it and rechecked it again.

This particular build has over 20,000 miles of hard track testing on Shane's personal CTS-V.

Also, don't think that I can't afford heads (it sounds like you're basing your "money" statement on that). They don't make sense from a price/performance perspective.

-T-

iTrader: (2)

I think you're taking it a bit personal than it was meant to be. Money as in, it costs to do head work and most people have budgets. Ballers like you wouldn't understand I guess.

With a higher lift, you are changing the valve angle slightly causing more wear on your guides that are right now in an unknown condition. It is cheap insurance to get a valve job and replace the guides rather than have an unanticipated failure.

60 hours and checked and re-checked---- you failed to notice your valve locks weren't properly seated. People make mistakes all the time, after hour 24 I'm sure you were ready to have it completed. FWIW, it took me 14 and I had my heads worked over by a local machine shop. You spent more time trying to keep just one valve from falling in the cylinder than it would have taken by pulling the head. And having an expert check the install doesn't seem that illogical to me! How many can swaps have you performed?


Good heads will net more power per dollar than full exhaust. But you ponied up that couple grand. Now what makes more sense? 2500-3000 for 20-35 rwhp, or 2000 in heads for 50-60 rwhp after your cam install?????? Not seeing your "perspective".

FuzzyLog1c

iTrader: (4)

First off, 60 hours includes the following from someone that had never done any of the following:

- Front bumper removal
- Headlight replacement (color temp test)
- Radiator, power steering, and A/C flush
- Racetronix Hotwire kit relocation from battery to alternator
- Crankshaft pin
- ATI SuperDamper installation
- New water pump and timing cover seals
- New camshaft
- New valve seals, shims, seats, springs, retainers, locks, pushrods, and rocker trunnion upgrade
- Construction of a piston stop
- Construction of a custom harmonic damper installation tool
- And the time it took to disassemble, check, and rebuild the valve train 2-3 more times.

I didn't notice the missing valve spring lock (and i doubt you would've either) because it was the #8 cylinder next to the battery and the lock in question was rotated away from the front of the car. The cause of failure could have been either the collet effect or improper seating. More likely the former. I didn't spend any time trying to keep the valve from falling into the cylinder. Set cam to BDC --> done.

I appreciate your concern, but I'm confident in my installation and I believe I've done the right research and testing to reduce technical risk to a degree that will give me years of trouble-free operation. I'll be keeping and eye on those valves, though. The wear and tear on the valve stems will eventually take its toll.

-T-

iTrader: (2)

Wow! You set your cam to BDC and your valve never fell in the cylinder when you removed the spring? Magical work. Edit: removed harsh comment

FuzzyLog1c

iTrader: (4)

Perhaps I used the wrong term. TDC for the #1 + 360 degree crank rotation = TDC for the #6 cylinder and what for #8 intake valve?

I obviously didn't mean bottom dead center of the #8 cylinder.

RADEoN

iTrader: (12)

pump the cylinder full of air and your valves won't fall!

FuzzyLog1c

iTrader: (4)

Of course. However, Darkman did a quick check and identified that the LS2 valves are 4.867 inches in length compared to a stroke of 3.62 inches. Therefore, it's pretty hard to drop a valve when you're cranking the motor over by hand.