Old-style glow plug questions...
 

About 2 months ago I put the engine from my smashed and dented '75 240D into a much nicer '75 240D body; ever since then it has been much harder to start. I have to glow for much longer and crank the engine longer as well. Last night I accidentally forgot to heat the plugs for any length of time (had a lot on my mind) and the engine seemed to start just as well as it normally would WITH glowing... so this morning I went out and intentionally started the car without glowing at all. It wasn't any harder to start than it has been when using the plugs. This tells me that the plugs aren't doing anything; the thing is that the glow indicator still works. Does this mean that the plugs are heating up? Or will the plug indicator still glow even if the plugs aren't working? I thought they were all in series, so if the plugs aren't working the indicator won't glow either...