it is possible its knackerd,but these pumps make that noise when their is air being sucked in,i.e it would make that kind of noise if you had nearly ran out nof fuel for instance,or if a line was split,but one common thing for this is the block on the drivers side of the engine,right at the back,near the bulk head,check thats not leaking fuel,cause if it is,air is getting in,causing your pump to run dry,hence the noise,check the oil as well,as the injectors are inside the head,and can leak diesel into the engine,you will see a rise in the level if thet are leaking,hope this may help,jim.