the white wrap over the fuel lines is to prevent vapor lock. Helps to shield the fuel lines from the heat, so if you land, the heat that builds up can make the gasoline in the fuel lines bubble up (maybe?? I do not know about this, but have heard of it).
IF I fly, in 95 degree weather, then land, my motor will turn on 1 minute later or 10 minutes later with no problems.
But, I have heard of some people whom their engines will not crank up.
But on all my recent airplanes, I have done this trick. I cannot prove it works, but I have not had this problem.