help

Hello,

I am new to the site and need some help with my 84 D50 Diesel. It won't start. I was drving down the highway and the engine stopped, and I had to get it towed. already replaced the fuel filter and checked the timing marks and belts and they look fine. I also checked the fuel shut-off solenoid and I can hear it click. I do get fuel out of the injector lines at the injector when I turn over the engine. Does anyone know what the other electrical lines running to the injecor pump do? I also check the glow plugs and they are fine, even though that would not cause the truck to stall and not start. Seems to me like it has to be something with the injector pump. Thanks for any help. Taylor