Hi David - Can blow through inlet manifold (Jiggle) pipe, can blow through all pipes from the 4 Way Junction. However, as I had to release some coolant to gain access to the pipes, I found in the bucket a hairy-thing!!! Quite large so it must have come out of the pipework somewhere. Even disonnected the radiator bottom hose and when blowing through the pipes it drives water out of the lower hose.
Need some more coolant, so off to Halfords. Will probably get it back together tomorrow, or thursday, so will let you know the outcome.
Cheers for your help.
Robert