How do you stop vapor lock?

[tbirdtbird]

That is a very workable solution if you can arrange it. I have seen that done on several restorations, but none were As. One was an Amphicar. The problem for an A is just where would the return line go, and an electric fuel pump would have to be added for pressurization.

Another thing that we Texans do is to put the Zeniths on the shelf and roll out the Tillies. Tillies don't vapor lock even with crapahol gas. Die cast gives up the heat, cast iron soaks it up

 

[emf]

I'm going to try that in my Studebaker, because it takes some cranking after it sets for 5 minutes to a couple hours when hot.

Have you tried any clothespins???

 

[updraught]

From the same web site as the book, in the tech tip section:

"Hot drivability/hot restart problems are primarily warm weather problems. Today, the EPA regulates the vapor pressure of all gasoline during the summer months (June 1 to September 15 at retail) resulting in maximum permitted vapor pressures ranging from lower than 7.2 psi to 10.0 psi depending on the type of gasoline and area in which it is sold. Therefore hot drivability and hot restart problems such as vapor lock and fuel foaming have been largely eliminated (except for antique vehicles) for modern cars and trucks. All of us who drive antique vehicles with five pounds of fuel pump pressure still experience drivability issues. The alcohol in the fuel also dries out gaskets in the carburetor and fuel system.
The alcohol can also cause damage to rubber fuel lines and the rubber diaphragms in mechanical fuel pumps. We buy less than one percent of the gasoline sold in the United States so we are pretty far down on the food chain."

http://fifthaveinternetgarage.com/pdf/RefiningModernGasoline.pdf

 

[John Stone]

IMO the gas line is really not the problem. It is the carburetor getting too hot and causing vaporization. MMO usually works to a point. I know I never had the problem until the alcohol gas came on the market.

 

[Tom Wesenberg]

IMO the gas line is really not the problem. It is the carburetor getting too hot and causing vaporization. MMO usually works to a point. I know I never had the problem until the alcohol gas came on the market.

Exactly right.
My Stude and other cars I owned never had problems until the late 80's. I have some white wire wrap that I put on my Model A when I had to use the crap gas, and the white wrap did help, but wasn't a total cure. Gas without the corn crap was the total cure for the Model A. The carb on the Stude gets hot because it's right over the exhaust manifold and preheater, and the fuel today will boil in the bowl, so the intake is flooded when I try to restart the engine after a short stop at the store.

Some nice asbestos wrap on the exhaust would probably help, but the EPA, in their ignorance, has banned it. I'll have to see if there is some other kind of wrap that might help.

 

[Cool Hand Lurker]

I think aluminum clothes pins would help.

 

[1931 flamingo]

part # and source ??

Paul in CT

 

[emf]

How about these:

Aluminum Clothespins

 

[Safewiz]

Just a thought, but I had a bad vapor lock problem that stemmed from the heat from the manifold transferring to the carb. Caused the fuel to boil in the carb. I put a heat sink plate between the manifold and carb. Solved my problem. And I had a electric fuel pump as well. It was half inch thick and made out of wood.

 

[Cornishman]

Refering to a Pepsi as a Coke?? Blasphemy!

I thought he meant; drink the Coke, pour the Pepsi on the carb.

 

[Brian T]

This is the way I have mine setup, this heat shield dropped the carburetor temperature down 40* from 160* to 120* on a 90* plus day when I ran the Zenith, the phenolic spacer takes care of heat transfer after shut down with little affect to the carburetor, engine starts without any fuss.