Posted by Johnd [172.69.62.61] on Sunday, February 10, 2019 at 07:25:49 :
In Reply to: Re: liquid vs vapor posted by clueless [172.68.78.85] on Saturday, February 09, 2019 at 19:19:24 :
The difference between liquid vs vapor is a function of the tank. A lot of propane tanks have two ports, one labeled liquid, the other vapor. The vapor port is just a threaded hole in the tank. When the tank is installed in the vehicle, the vapor port needs to be on top so it only receives the air above the liquid, thus the name vapor. This vapor can be plumbed directly to the carb. The liquid port has a tube inside the tank that goes to the bottom of the tank, thus supplying liquid to a heat exchanger. The heat exchanger uses engine coolant typically to convert liquid to vapor.
You can see why the liquid system is better for a vehicle to get the most miles per gallon of LP.
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