1980 1.5liter Diesel I relaced glow plugs, it ran OK, then it just wouldnt start. So I checked the fuel situation, and the inj-pump is getting fuel,I changed filters for grins, It will crank and stay running when prime started w/WD-40. It also has no power-like 40-45 mph going up hill and top speed is maybe 55mph, it smokes white smoke and I cant figure out why the problem with the starting? I feel I need to replace injector nozzles/I tried Diesel purge stuff you run straight to inj. and No change in engine. anyone got any suggestions I NEED HELP