Help. I just pulled the plugs and I found oil in the hole, at the base of the plugs where the spark happens. What could be causing this? 1970 Ford Ranch Wagon 351 Windor (Replaced 1989'ish)
It can be the rings, or the valve stem seals. The seals can be done, using a length of clothes line, a manual spring compressor and a small magnet. Any manual will tell you how to remove the stem keepers, the spring cup and spring, to replace the seals. The rope, you put about two to three feet of line down the spark plug hole, then rotate the engine so the piston pushes the rope against the valve heads. That way, they won't fall into the cylinder once you release the stem keepers. And make sure you do all sixteen, so that if you do also have bad rings, you'll know.
