Thanks for all your work here Steve. I too was dismayed to see at least £280 for a spare motor and/or the extra cost of an engineer visit. Followed your guide and stripped it all down and cleaned stuff up. The inner bearing on fan 1 had corroded to the axle and had a fair amount of play and there was a heavy build up of gunk on the fan,
I needed a bearing puller and this worked a treat - 75mm puller