[Spridgets] 1500 Fan Clutch question

[David Booker]

My friend put a new fan clutch and water pump on his 1500 Midget this weekend.
The clutch went onto the pump shaft via his press, feeling what he thought was
properly "snug" during the process. Everything went back in fine, using all
the 
proper parts (there's apparently a crush washer in there somewhere, but
I've 
never worked on one of these so don't know).  A few miles later when
everything 
was nice and warm, the fan went into the radiator...

He wants to
know if this is a common occurance.  The pump and clutch both came 
from Mo$$.
Anybody have suggestions for a fix? JB Weld on the shaft when 
reassembling?
Drill and tap threads into the waterpump shaft, then lock on with 
a bolt and
washer? Other ideas?

He didn't like my suggestion of throwing the whole thing
away and installing a 
thermostatically-controlled electric fan as he fears
the alternator is not up to 
the task...

Thanks,
 - David Booker