Tractor Repair: CASE 1370 engine oil goes into transmission, crankshaft seal, radiator cap

Question
i've had this 1370 for 3 years, no longer do heavy field work with it, just cut/condition and bale hay. a couple of years ago it started forcing the engine oil into the transmission. i have to keep adding engine oil and every once in a while drain some transmission oil[obviously a mix]. it hasn't effected the operation of the trans, and if it sits for 3 or 4 months, the engine oil level comes back up. anything simple to do to stop this? this may or may not be related, sometimes when i start the engine it will force coolant out the overflow. when it does usually shutting it off for a few minutes and restarting it solves the problem. am now running it with the radiator cap loose.

Answer
Hello,

  The coolant coming out the overflow is a separate issue, either caused by the radiator being overfilled, or a leaky head gasket or a small crack in a cylinder head or the top of a cylinder sleeve allowing engine compression into the cooling system.
  The rear crankshaft seal leaking is the only way engine oil can get into the transmission.