AEG Lavamat 74620 fill selector washing machine?

My AEG Lavamat 74620 washing machine suddenly would not fill at the start of a cycle, making just a clicking noise. Investgations revealed that there are a set of 3 cogs - yellow, white and orange - on top of the water inlet. They were 'slipping' with a click. The orange one appears to direct filling water as appropriate for the part of the cycle, the yellow one is the 'drive', the white one is a slave. They need to be assembled each in a correct position. I've got the machine working after a fashion, but can anyone tell me how exactly the three cogs assemble?

fill selector