Tractor Repair: 1070 case, broken rings, cylender

Question
My 1070 case tractor is missing on one cylender (3rd from front). Tractor starts good even at -30 but runs rough and loud The inside of the exhaust pipe seems to be oily. It also seems the level on the oil dip stick is increasing slightly. Pretty sure their is no water in oil. Suspect I may be getting a bit of fuel in oil. Any way to pin point problem before pulling heads off?

Answer
 a misfire can be caused by a bad injector, an injection pump problem, or low compression.  From the symptoms, it sounds like there is fuel being delivered to the cylinder that is not firing because of the oily exhaust pipe and oil being diluted with fuel.  By loosening the injection lines one at a time, you can determine which cylinder is missing which it sounds like you have already done if you know which cylinder is missing.  Remove the valve cover and check the rocker arms, valve springs, and pushrods.  If everything looks OK, then pull off whichever head is over the cylinder that is missing and check the valves.  If the valves are OK, then there are broken rings or a scored cylinder.