What does the valve stem O-ring do?

[First opel 1981]

OK, I know this is a silly question but what does putting an O-ring on the valve stem actually accomplish?
I am rebuilding the head on what I am affectionally calling the "puddle jumper" and when taking the valves out I found one valve actually had an intact (though hard as a rock) O-ring on the stem. One valve had a bunch of pieces of O-ring material and the other 2 valve stems had nothing on them.
So, I got to looking and trying to figure out exactly what is accomplished by having this O-ring on the stem. It desn't seem to actually "seal" anything.

I know how the caps work but why even bother to have the O-rings?



BTW, the "puddle jumper" is not related to any Stargate thing. My former GFs mother called my first GT a puddle jumper because I could drive down their gravel driveway when it was wet without splashing even once.

[yellaopelgt]

this should explain it.....particularly post # 8.http://www.opelgt.com/forums/6a-engi...tem-seals.html
hth
Joe

[First opel 1981]

I looked all through the searches but didn't see that thread or I glossed past it because it was about installing it.
It's an interesting read up till about post 10 but you are right, post 8 explains it.

Now I understand that it seals the top cap but will still allow a tiny bit of splash lube to get to the stem without it running down... Or something like that.

Let's just say it makes TONS of sense now.

Thanks.

[Gumby]

Originally Posted by First opel 1981 I looked all through the searches but didn't see that thread or I glossed past it because it was about installing it. It's an interesting read up till about post 10 but you are right, post 8 explains it. Now I understand that it seals the top cap but will still allow a tiny bit of splash lube to get to the stem without it running down... Or something like that. Let's just say it makes TONS of sense now. Thanks.

It is good to think of them as an oil meter for the valve stem rather than a seal.