Rocker Arm & Pivot

Well... I started my car one day and drove a few blocks when I noticed a mechanical, metal-on-metal sound coming from my engine compartment. I drove back to the house and listened to find where the sound was coming from. I turned off my car & removed the engine sump to take a look at the camshaft and look for any problems.

What I found, was a rocker arm that wasn't clamped down to the little plate that sits on the top of the spring. That plate had dislodged itself and was sitting at the bottom of my camshaft. (Good thing I found it..) I'm going to take some pics in a few minutes. Waiting for the digital camera.

Basically, I'm wondering what could be done...? =\ I know I could order & replace the rocker arm & pivot but I'm not sure if it's that damaged or not. Does that little plate come off or did it "break-off?" Has anyone ever had to deal with a similar problem?