Problems come in threes.

[Rich Sims]

I think you were lucky to have found those issues with the head now rather than on a trip somewhere.

 

[Roger Fairclough]

Thanks for the comments and help guys.

It's amazing that such an ostensibly simple item can be such a bugger to diagnose, especially when spurious non genuine parts get in the way.

Anyway, one for the memory banks.

Roger