Hi, was just curious if this was a common thing. The seat/shim under the valve springs seem to have a tendency to stress crack. Has anyone dealt with this? Thanks!

 

Hmmm, I have not ever noticed any of them to crack. I wonder if they are aftermarket pieces.

I would measure the "step" on the cylinder head to see if maybe the head has been machined too much where the spring seat sits. The upper portion of the seat could be hitting/resting upon the valve guide "boss" before the lower seat portion touches the cylinder head.

 

Thank you for the reply Earl! I've seen cracked/broken seats on 2 different engines, and this looks like all stock (old) stuff. But sure, maybe they were installed slightly wrong, I need to check for that. I spent 2 hours yesterday pulling apart a cylinder head from junkyard and grabbing 4 valves/springs/seats/keepers. When I got home and cleaned them up for a close look - yep first one I found was cracked half way around. And these guys aren't available from RockAuto or your local parts store. From what I could tell, they would be special order from any dealer, and who knows when they would show up!

 

Cracked valve stem seats and or the springs retainer's is an indication that the valve spring is not rotating as it should be. I would suggest examining the spring for the source of the problem.

As for availability there is always a substitute for almost any vale stem seat or retainer, but you need to contact Performance camshaft companies to help you.

 

Thanks Callisto, sorry for the tardy reply. The springs _look_ ok, I also measured valve guide height, and they are within spec. So, has this happened to you?

 

Yes but a different engines. But my response was that retainers available you just need to change your source hunt and actually talk to a human by phone. If you are in need and cant find contact camshaft manufactures like Crower,Snider, BC Cams ect. You just may need to also have them supply a different keeper to adjust for spring height.

 

Thanks Callisto, but it's not the retainer on top of the spring - it's the shim under the bottom of the spring. I think I have enough good ones to suffice. Thanks!

 

I understand and both can be replaced with available ones. There is nothing special about your spring dimensions. You would be surprised how many harden lower spring seats there are available that would work in its place. As far as the top spring retainer there are much better option for springs as well keepers and retainer then the stock ones. But I suppose unless you were trying to boost the power levels than it would not really be of benefit unless you were routinely breaking any of them.