starting problem after run to full temp

I too have a 77 280Z I have that same problem. It's really irritating! I just had my engine professionally rebuilt and everything that went back was new with the exception of a fan clutch. I bought one as suggested. I also went to the Nissan dealer and got an OEM thermostat. It was also suggested to get a fan shroud. None of that made any difference because she stays cool when in motion, it's sitting at long lights or in traffic that brings the temp up. I think from here on out I am going to try an electric fan in hopes that it works better than the fan clutch and the diminished RPM's when at idle. Good luck with yours too, sincerely.

I have a 78 with same problem. When it's shut down the heat rises and will vaporize fuel in the lines. The bubbles keep fuel from moving through the line. In 1978 the put hood vents to let the heat escape. The 280zx came with an electric fan and hood vents to fix the problem.