[WINGY]

I know the pump well harry. Manual priming is needed on deisels after running out of deisel (i wouldnt know this from personal experiance honest). sounds like yours  has a seal down or something of that nature, if you find you need a new pump deisels are not cheap. Theres a firm in blackburn (think its walsh and midgely) that can recon or repair at a fraction of the price.
hope its sorted for sunday ;D