I went to install new valve cover gaskets and I noticed this aluminum rivot on the rocker arm is loose. I tried to see if it would come all the way out but I could'nt get it to come out. It is just loose. SEE PICTURE. Do you think this is bad?

 

Thats there to plug the drilled hole for oil lube to the rocker arms. Not something I would want falling out, you would loose oil to that set of rocker arms.

 

I would pull the arm and pivot and either peen the center of the aluminum plug to tighten it, or replace the unit. You do not want it rattling out.

 

What do you meen peen?

 

Peen = beat on it with a hammer.