Vapor Lock

[FlatheadTed]

I get the boiling point of gasoline at 185 F .We are talking about average sea level motoring .I think the fuel Co would be required to give out accurate information you can see the extensive testing they do .,here is some interesting reading .Ted

http://www.engineeringtoolbox.com/fuels-boiling-point-d_936.html

http://en.wikipedia.org/wiki/Gasoline

http://en.wikipedia.org/wiki/Gasoline

 

[rheltzel]

G.M found the boiling temperature of the gasoline in his settling bowl on a particular day at sea level (or close) to be 140-145 here: http://www.fordbarn.com/forum/showthread.php?t=61323&highlight=boiling+gasoline&page=2

But that boiling temperature would be much lower at my elevation and would be different for other gasolines and on other days. So, impossible to predict precisely.

While I can't say with certainty that my infrared thermometer is absolutely accurate, when I tested this a couple of weeks ago, I had fuel percolating in my float chamber at approximately 137F, well below the 185F temperature cited in Flathead Ted's posting. It is possible that reading is low, as the manifold (stock aluminum) was 185 - 190F. My elevation is about 75ft above sea level.

Regardless, it stands to reason that heat is not our friend when it comes to modern gasoline in old Fords, so anything we can do to keep operating engine temperatures low, at least to a point, the better.

 

[FlatheadTed]

Percolating gas can still be pumped ,what we are talking about is turning from a liquid to a gas even my 185 F is only boiling ! not a gas at that point .Ted

 

[Old Henry]

. . . it stands to reason that heat is not our friend when it comes to modern gasoline in old Fords.

That's why I finally caved in and installed an electric fuel pump. I am highly committed to authenticity, which an electric fuel pump is not. But, I finally justified in my mind installing one because we no longer have "authentic gasoline" that these authentic flatheads ran on in their day. I got tired of pouring water on the fuel pump when it vapor locked so bit the bullet and put in the electric pump.