[Yosemite Sam]

A 141 is an early 7 hp engine, it had a 2.785" bore and a 2.50" stroke as opposed to the later 161's that had a 2.938" bore and a 2.50" stroke.

If I am not mistaken there are no pistons and rings available to rebuild a 141, however the good news is that the block can be bored for a 161 piston and those parts ARE still available.

I personally do not know when they changed from the 141 to the 161 so I can't answer about if this engine could be original to the tractor, but I'm guessing it was.

Nice find!