E34 525 TDS issues!

[Rossco525]

hi there, i own a '96 bmw E34 525 tds. Last nite it started struggling to start from cold. takes about 20 turns, coughs then fires up. At first i thought it must be the glow plugs.
But on my way to work this morning i started loosing power after about ten miles, like it was struggling to take throttle, that lasted all of about 10-20 seconds. Another ten miles or so down the road it happened again, but this time the injector light came on, once again after 20-30 seconds it cleared and kept on going.
But 5 minutes later it cut out and the car rolled to a stop then wouldnt start for a couple of minutes. when i finally got to work i popped the bonnet and saw a lot of air bubbles flowing through the see-throught fuel line from the filter to the injectors.
Im now on my lunch break so ive just been out and started it, it started fine and there was no bubbles, untill i gave it throttle. there arnt as many bubbles as earlier but still quite a few. Please help me with this one, ive only just started this new job on monday and dont want to break down on my way to work tomorrow! im thinking that maybe its drawing air through the fuel lines?
Any help appreciated, cheers!

[Jack Dabsy]

Could be a diesel pump seal my friend...