Turnip finally given up the ghost.
My shed was tidied at somepoint without my knowledge and it looked like a connection to the rectifier came loose. Then over speed and then blades falling off. Thats my post mortem anyway. Not got the PMG down yet to have a look at it.
I could probably fix it but tempted to use the PMG for something else.
Front fell off!
The black (Istabreeze) 500w blades vs Navitron 300w Guess that'd be why it never generated more than 150w in a hurricane then.
Bodging 12v self regulating turbine to be normal turbine (Temp installation until I get some rectifiers which actually fit properly

Still breeze today so stood up on top of the berm to see if it would actually spin fast enough to put out 24v and it seemed to belt out the amps pretty happily.
Thanks to Navitron for the massive pile of turbine stuff.
When I've got it flying will post some more pictures.