Good idea. If you want to see the Block Tester in use their is a fellow on YouTube called Monkey Wrench Mike and he posted A video a couple of days ago testing his engine for combustion gasses leaking into his radiator. He's got a bad one there!Thanks for the tip harleyron74. I ordered the Blackstone Laboratories oil analysis kit and will send it in to see what they say.
Again, good luck on your tractor!