Bongo Fury

My fan just works when it feels like it - do I need a resister or a new motor? How can I tell?

Check the Factsheet in the members area, it should get you sorted if it's the resistor pack. Is it just working on certain speeds?
Take off the front intake to the fan & see if it rotates freely (power off). Is the drain under the windscreen blocked causing water ingress on the fan or resistor? If the resistor has gone/going, it could be that extra load is being placed on it it due to the fan starting to fail. good time to whip the fan out & give it an overhaul, only takes a couple of hours

Thanks Kirsty. Very helpful.