My 79 300D is still very difficult to start. I replaced all the glow plugs, adjusted the valves, and changed both fuel filters. It's 32 F. outside and she's plugged in, but still no go. It's my understanding that the glow plugs turn off when the starter is engaged. Would it make sense to start over after every five cranks or so to heat the plugs up again? Also are the preformed solid wires between the glow plugs supposed to get so hot that they can burn you real good? Even though all my plugs are new, I've got this feeling they're not working properly. Does anyone know a proper test procedure? Thank you, CJ.