Originally Posted by
Brute
There is a little knob just in front of the Hi/Lo lever, lift it up to open the flap to let air though the heater, has 2 positions on a detent. If you have air while you are moving it must be open anyway. My heater motor had a bad earth so might be worth checking that if the fan isn't working. Also my switch is a bit temperamental and needs 2 goes sometimes.
We will have to get the 3 101s together when they are all road legal. Maybe book them all in at the pits together:)