diesel running rough

[fillmore]

my 89 diesel non turbo is running rough latley, when i start it it rolls over and over and fianally starts after a couple tries, once it starts it runs like *** unless i pull the cold start all the way out, than once it warms up it will idle fine. i know that its a problem in the fuel system somewheres but i dont know where. the guy who owned the car drove it like *** and redlined it lot so im assuming he screwd something up pretty bad. however, the timming belt is new and it is nice and tight. when i shut the car off sometimes i can hear air hissing and when i look i can see gas with air bubles getting siphoned back through the fuel ines into the tank. does this mean that my fuel system has an air leak somewheres?
thanks,
myles

[BlackTieTD]

sounds like there could be an air leak either in one of the fittings, or one of the seals in the pump possibly. go around and try to see any wetness from fuel, (use brake or carb cleaner to clean it up first if you want), and tighten down and loose connections. its a start..

[fatmobile]

It could even be a leak at one of the little lines between the injectors.
 They can let air in and fuel will flow back to the tank.