fan belt 1927 hudson

Unknown

hello again

I had just replaced the fan belt on my 27 Hudson with a modern rubber belt

(this could have been a mistake)

I took the car out fr a spin when I hearda noise under the hood. The fan

was spinning and hitting the radiator

the fan was flush against it! So my question is what stops this from happening. I can see no retainer on the shaft to stop it. No nut at the end of the shaft. And if it is broken,

do I have to pull the radiator to get it out? As you can see, I need help

Any kind of help thanks John T