I have a Cub Cadet 107 with weak motor and wondered what model motor it would have? I also have a block with piston, crank and valves in it but wondered how to tell what model it might be without a data plate
The official KOHLER K-SERIES SERVICE MANUAL available FREE on-line shows how to build a U-Tube MANOMETER to check the amount of vacuum the engine creates inside the block when running. I've found it to be the best way to check engine condition. Guess that's why Kohler put it in the service manual.
Only way to perform a compression test is to spin the motor over BACKWARDS from normal rotation direction. I've never tried it, if somebody does try it, please post your results.