The step-by-step guide is basically "pound the old one out and pound the new one in". You can get a complete set of core plugs, (aka freeze plugs), for your specific engine at any auto parts store, or they can look up the size you need and sell you just one. Many parts stores now borrow or rent tools and they will have a kit for installing the new plug. It's just a pair of extension handles and a variety of discs. You pick the disc that matches your plug, and use the handle that gives the best access.
Clean the hole out first of any rust or scale. I like to add a little bead of gasket sealer around the new plug but I doubt that helps much. It's not necessary. If you have a straight shot at the hole you might get the new plug in with a socket that just matches the diameter of the lip. Don't insert it too deeply, and don't hit it in the center. That will deform it and shrink it causing it to leak.
Usually core plugs corrode through and don't completely fall out. You might look if there was a block heater in there. It will be hanging nearby by the cord. Sometimes the wing nut that holds them in breaks but the heater won't push out until the system builds pressure.
You can also buy rubber core plugs that tighten down with a wing nut. Those are nice for places you can't reach without removing a lot of other stuff.
Thursday, June 6th, 2013 AT 2:54 PM