ZeeOSix

During my PAC 1518 spring install today, I discovered a cracked OEM spring retainer on the Cyl #4 Exhaust valve. Did a quick visual check on the other retainers on the RH head and all look OK. Haven't looked at the LH head yet.

Looks like there might have been a large ding or flaw on the edge of this retainer that caused a stress riser. In the 2nd photo, you can see the crack running from the edge towards the center of the retainer.





So ... question is: Does anyone make a better quality, exact direct replacement retainer that will use the OEM split keepers and give me the same exact spring installed height? If so, then I'd probably replace them all with something aftermarket. Open to any suggestions.

If not, then I think I'll just get a new OEM retainer from the Chevy dealership. I'm hoping this was a freak occurrence due to a dinged or defective retainer during manufacturing. I'm the original owner of this Z06 (currently has 21K miles), and the motor has never been open until now.

ZeeOSix

Decided to look at everything now ... even the split keepers. Well, look what else I found. One of the keepers on the same valve that had the cracked spring retainer is damaged! I'm thinking this could now be related to the damaged retainer. Looks like the keeper was forced in during assembly. Still going to inspect every last retainer and keeper now. Lucky, this was only the 2nd cylinder I did ... so will only have to go back and remove the retainers & keepers on Cyl #2.

See major material smear and crack on bottom lip of keeper. I inspected the tip of the valve where the keeper groove is, and there doesn't appear to be any damage.



The keeper on the right is the top of the damaged keeper. Looks like some kind of tool had impacted the top lip. Wonder if a machine puts these in at the factory? Had to be factory damage, as this engine has never been opened up since the day I bought this car new.

zipster

iTrader: (5)

Thats weird. I have a new set if you are interested. pm me.

O2Form

You better check that valves lock land area carefully, could have damage too.

ZeeOSix

I looked carefully at the valve stem where the split keepers lock in, and the valve groove looks OK to me.

joecar

Did the rocker somehow miss the valve tip and come in contact with the retainer and keeper...?

ZeeOSix

Seems impossible since everything else in the valve train looks good. I think damage during engine assembly caused this. Found a local Chevy dealer who has some retainers and keepers in stock ... so will replace any damaged parts and keep on with the spring install.