My '78 C3 always had a niggling problem where when left for a while it would usually take 5 to 10 seconds cranking over to finally start. Thought it was either a carbie (tuning) prob or maybe a cracked fuel pump diaphragm allowing the float bowl and line from the pump to the carbie to siphon dry.
Bought a new fuel pump, and could only find one made to suit up to '74 models. It has one less line on the bottom. Realised that the extra(third) fuel line on my original pump was in fact the culprit by design. Seems it, via a tiny orifice, is designed to siphon the fuel in the float bowl and fuel line and return it to the tank when the engine is off- prob for pollution reasons (escaping fuel vapour???).
So on with the new earlier pump and now she fires instantly even after sitting overnight ;)
