Reply To: fuel pump pressure


Bill, I covered this in my articles on vapor lock a few years ago. Yes, the fuel line pressure has no influence on carburetor boiling. which is why a simple electric pump system doesn’t actually help with this. I am not a fan of insulation on the fuel line or the carburetor bowl to help with this, except for radiation shields with air gaps. The problem is that insulation slows down the transfer of heat but doesn’t stop it, so if a car heat soaks after a hot drive it will still heat up, just more slowly. Moreover, the insulation wrapped on a fuel line is going to absorb more heat radiating from a hot exhaust manifold than a shiny metal fuel line. The stagnant air under the hood rises to over 200 degrees for an extended time. When you get back in the car the insulation that slowed down the temperature rise of the carburetor bowl or fuel line now slows down how quickly it can cool down from the air that should start blowing around at around 130 degrees if you can get it going. The insulation’s effect of improving or exacerbating the problem becomes a question of how long the hot car sits before being restarted.