Seal inside valve cover

I just replaced the valve cover gasket (and spark plug well seals) on my '05 Legacy GT. The job went well, and as I was cleaning up my mess while idling the car, I found a little circular seal, about 30mm in diameter, on the floor by where I cleaned up the valve cover. I'm afraid this is the seal for the variable valve timing return line. The car idled fine for 20 minutes, but I never revved it. I'm afraid that if I rev up the engine and the valve timing control solenoid opens up, the oil will fill up the camshaft/valve space and I'll have serious problems. Is anyone familiar with this seal? I can't find it anywhere in the manuals. The inside diameter is 28mm, and the outside diameter is 35mm.

Help! Thanks!

You say seal, is that a metal washer?
Did you change the oil or change spark plugs at the same time?

That looks like it may be the diameter of the oil drain plug... is it the crush washer?
The oil control solenoid doesnt need to be removed to change the valve cover and doesnt use a metal washer, it has a rubber o-ring.

My first guess is a spark plug crush washer.

Can you get a picture of the side of it, does it look like it has two layers ?

Also aren't the crush washers for banjo type bolts copper ?


I'm also bad with mm to inches. Is 28mm just over a 1/2" ?

If it's bigger then that, I'd guess oil drain plug washer like MAP said.


Thinking about it, isn't 2.5cm = 1 inch ? The oil drain plug is 20mm so something with a ID of 28mm is going to fit on it.

Um, yeah, it was the seal from a little oil can. Forgot I filled that in the same place I cleaned the valve cover. Sorry.

On a different note, the valve cover job didn't go as well as I thought. Leaking badly up front. Dammit. Doing the clutch in a few weeks, see if I can do a better job with the exhaust removed.

I suck.