The one behind the camshaft is an oil gallery plug. The plugs that are dished are installed in the convex orientation. The idea is to flatten it out some so that it expands. It sits against a little lip in the block. I would use some type a sealant, maybe locktite.
To remove them you can use a small punch. Put a hole in it and lever it out.
In the factory they had a tool to install them. If one has been replaced, it might look a little different. Also, I think some of the plugs are the type with sides and they are installed with the face inwards.
Last edited by truckernix; 06/25/2010 10:45 AM.
