Yeah, back when I was adding my heated washer mod I took the NR valve off.
With the non-return valve gone, does it take a while for the washer pipes to refill after a long period of not using them?
A tip I was given by an MOT inspector is to always use the same brand of windscreen washer fluid to prevent gunge in the pipes as the different brands have differing additives and these react to produce the gunge.
Thanks. 'Talking cars' (James) got me going on this mod when he mentioned how his flow improved dramatically.........................