Thanks for all the input, I followed members advice and checked if there was fuel in the line and there was not. Gunk in bottom of tank was the cause of the problem, should have known it wouldn't have been a Datsun fuel pump those things go forever. I poked a stick up into the blockage and ended up covered in petrol, I now have a big soft patch in the asphalt but the car is going again.

Thanks Greg for the offer of free fuel pump, its much appreciated, when I really do need one I know who to call.