I am hoping someone can advise if the "key" in my photos is meant to be free floating around the end of supercharger shaft? I assume when the water pump is tightened-down, the "key" is pressed against the shaft collar and/or uses friction to turn the water pump?
I've been round and round with this cooling system. Had boiling coolant to start...
no coolant in oil and no oil in coolant
no exhaust gases in coolant
changed thermostat
changed water pump
changed radiator
changed resevoir and cap
changed heater core
system bleed seems successful, several warm and cool downs and coolant added, only fluid from both bleeders
No more boiling coolant after changing the heater core, it was fairly nasty. However still overheating once warm and held at a sustained rev ~2-3k RPM or driven a very short distance. The upper radiator hose gets hot. The upper hose to heater core gets hot. Very minimal hot air from blower. I've opened the upper bleeder screw and have seen flow. Any input is appreciated.

SC to WP exchange key "free floating?"

 

Looks like the pump drive is toast. Split it open.

 

Ok, ugh. Should the pump drive collar be seperated from the shaft? I see photos elsewhere of the shaft/collar seperately and what seems to be one piece.