Small Engines (Lawn Mowers, etc.): lawn tractor, crankshaft diameter, engine shaft

Question
On my murray I took off the Engine, there is a 2 pullies below, one was the drive and the other is the blades belt. Can I remove these and use on another engine, I din't see any set screws and they appear to be a one piece unit that goes on the engine shaft.
Thank You

Answer
You should be able to use this pulley (it should be one piece) on another engine provided the crankshaft diameter, crankshaft length (and length from end to shoulder) and keyway are the same.  If you are replacing with a similar HP engine, these sizes are often common between engines and years (but not always!)  Hope this helps.