Small Engines (Lawn Mowers, etc.): Cub Cadet Problem, drive shaft, spec number

Question
Hello, I have a 1993 Cub Cadet model 2185 mower with the 18HP Kohler engine. It has a serious vibration. After thinking it was the engine, I have determined that the drive shaft going from the engine to the tranny is loose at the back of the engine. What is this part called, bushing, collar?, and what do I have to do to install it?
Also, another problem it just started is, oil is coming from the engine through the carb into the air filter. The engine was very hot and no oil showed on the dipstick when the engine was shut down. It registers full after cooling off, but the mess of oil on top and around the engine compartment. What to check?
Thanks for any advice.

Thomas

Answer
I believe you are talking about the drive adapter on the drive shaft.  Below is the link to the parts diagram for your mower:

http://www.partstree.com/parts/?lc=Cub+Cadet&mn=2185+Tractor+S%2FN+239%2C001+-+3...

You can loosen the engine or remove the drive shaft to replace the adapter.

The Kohler engine will have the engine model number located on a sticker.  The sticker is on the engine.  Please send me the engine model and spec number so I can look up the manual.

Eric