A compression test will determine whether or not you have a bad cylinder, but a Borescope will have to see whether it's a bent valve or a hole knocked out of your piston dome. (If the compression test does in fact prove that you have a bad cylinder.)
You're not going to want to hear this, but the rods have a small pin hole that sprays oil up under the pistons to lubricate the rings and wrist pin. If you've got oily plugs, you may in fact have a big enough hole in your piston dome(s) that that's where the oil is coming from. How many of the plugs were fouled?
Perhaps you can find a nice engine in a local junk yard and have it changed without it costing you an arm and a leg.
Friday, December 16th, 2011 AT 4:03 AM