A Datsun I had in the 70's has a thermostatically controlled fan
directed at the carburetor. After stopping in a parking lot for about
15 minutes it would vapor lock and not start. Changed fan wiring to
bypass ignition switch so it would run until cool and no more problem.
--
Gene Seibel
Tales of Flight - http://pad39a.com/gene/tales.html
Because I fly, I envy no one.