Dumb question

[JeepsAndGuns]

This might be a dumb question, but what is vapor lock? I have read on a few diffrent posts where people were talking about fuel pumps and vapor lock. I have heard of vapor lock before but never really knew what it was. Please forgive my ignorance. Thanks

[River Beast]

the vaporizing of fuel from liquid to gas within the fuel lines... can be caused from heat and/or vibration of fuel lines.....

the fuelpump can only pump fluid... not vapors of gas

[will e]

It is not a dumb question.

Actually the term is a little mis-leading.

What happens with vapor lock is the fuel in the line 'boils' into a vapor. This makes it difficult for the fuel pump to pull and, as a result, you have loss of fuel pressure.

This is one condition that an electric pump placed inside or as close to the gas tank as possible can eliminate. Since the fuel is pushed (pressurised) it not only raises the boiling point but pushes the fuel along.

[ September 07, 2003, 08:33 AM: Message edited by: will e ]

[flatbackdragon]

and insulating the lines as much as possible helps also, so many come to the higher elevations here in colorado and on a warm day, up there 80 is WARM, vehicles vapor lock, yet my old 79 and carbed 401 keep plugging away. keeping heat from exhaust, engine heat going below the vehicle, away from the fuel tank will make a difference too, even the return line to the tank heats the gas, so any means to keep gasoline in liquid form helps, as electic pump or manual pump needs liquid to work, as will e said.

[Mikel]

Higher pressures (lower altitudes) tend to condensate liquids, which tend to evaporate when the pressure decreases. This is why a pump capable of more PSI prevents the gasoline from evaporating.

[JeepsAndGuns]

Cool, thanks for the info.