Rear Heater Fan to shaft connection?

[AK72IronPig]

Trying to rebuild a crunched rear heater on my 4/72 Pig and the fan is free spinning on the motor shaft, was there a set screw there? shaft is not drilled thru to pin it. I appreciate the assist.

 

[rkymtnflyfisher]

Set screw.

 

[Shark56]

No idea if it is the same as a 40 series but here is a pic of one I am just now sitting here cleaning up.
Small set screw on fan. Shallow indentation in shaft.

 

[AK72IronPig]

Perfect! Thanks for the assist. Yet another mission in my future.