What is this Part?

[haubest]

I have a 1997 Ford Explorer XLT 5.0L Fuel Injected. The truck had a broken lifter guide retainer spring but I thought it was something more tragic. I was going to pull the engine to get to the oil pan. I pulled the heads off and in one of the heads I found two of these small round "spacer" sort of things (see picture) that I have no idea what they go to. They are not part of the valves. I'm thinking they may be part of a connector to a line of some type. The part is about 3/8" in diameter and 1/16" thick.
Thanks for your help

 

[Turdle]

That is a valve cover gasket spacer-it came out of one of the bolt holes in the gasket. They keep the gasket from getting smashed. Take a close look at the old gaskets so you can account for all of them.

 

[haubest]

You're right. I looked at a new gasket and there they are. Never would have guessed. I threw out the old gaskets but I'm pretty sure I got the all. Thank you very much. I was a bit worried.