Possible Vapor lock hard hot start solution

The more I think about the heat shield, from Dick Spadaro, the more I like it. In fact, I think it should be larger and made of asbestos ! (Yes, I know all about asbestos).
Most "vapor-lock" stopages occur after the engine is shut down. The problem happens on the re-start. The gasoline will boil from the radiated heat from the engine. I have actually seen boiling gasoline in my own car ! That is a little scarey !
MIKE :)
 
Dick...I'm pretty sure that the comments of "coil fixed my Vaporlock problem" were tongue-in-cheek.

I/e 90% of carb issues are ingnition related and 90% of ignition issues are carb related ;)

PS...this isn't a new concept, my folks '77 Winnebago (built on a Dodge Chassis with a 440 in it) has the same type of shield under the AFB carb. The sheild had the "MoPaR" stamp on it with some part number as well.

I guess what I'm saying if OEM's used this I'd bet it was tested and found to help, or they wouldn't waste an extra buck on anything mass produced.
 
You would think we would have a lot of vapour lock incidents down under since our Old Fords have the fuel line running parallel the full length of the exhaust on the left side. But we don't ??
 
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Several months ago I fitted a 500 Edelbrock carb on my 8BA. A couple of months in (when our weather was heating up) I had a massive flooding episode which turned out to be a leaking brass float. Seems the heat sink which occurred after I'd arrived at work & switched the engine off was sufficient to melt the solder holding the two halves of the float together. Along with a new float, I fitted a heat shield (approx 3/8" thick) between carb & manifold and have done heaps of miles in stinking hot weather without a further problem. Long may it continue!!
 
Back in the 60's when I was driving my '39 coupe to college, I had a 150 mile trip from my home to where I attended college. I always removed the side panels when the weather got warm to help keep both the engine and passenger compartments cooler. I had no problems with vapor lock until I would stop for refreshments. If I stopped for a Coke the heat would soak the carb and fuel pump and vapor the gasoline and vapors will not pump. I would finish my drink and then I would place the cup of ice over the top of the fuel pump. By the time I got back in the car the fuel had cooled enough to return to a liquid state and I could then start my car. No, I didn't have to cool the coil, it was a vapor lock in the fuel system. With they new "Corn" based fuels I am sure that this problem is only going to worsen so, be prepared and have a Coke!
 
I believe the heat sink will do what you are saying, but won't it only slow down the boiling of the gas. Once the heat has saturated the envoirnment under the hood the heat sink will cease to function or be reduced from its initial insulating curve. ??
 
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I am kind of confused. If the fuel boils out of the carberator and the fuel line the needle valve should be open. The fuel pump would only need to fill the fuel line from the pump and the fuel bowl on the carburator. This will take a little more time than a cold start. This should not be a big problem with a good battery.

The fuel pump would have troubling pumping fuel if the fuel in the fuel line from the tank to the pump is vaporized because of heat. The vapor lock would not be on top of the engine. The fuel line from the tank to the fuel pump would be more likely to have the vapors instead of liquid because it is being sucked and heated on a warm day.

What am I missing or not understanding about vapor locks?

Got good news= The 39 has been setting for about five months and It started with nobody blowing in the tank. I wish I could remember where I bought that new fuel pump. I think it was Macs.
 
Read this article

The addition of ethanol, as well as increased oxygenation, and the removal of lead, has lowered the boiling point of pump fuel significantly in the last few decades. Boiling fuel is the cause of vapor lock, a common problem with older carbureted cars. New cars are built to compensate for this change, but older cars weren't.

The fuel boiling point can be raised by pressurizing the fuel, using a high-pressure electric fuel pump located close to the fuel tank.

Lead additives, where legal, can fight the effects of ethanol gas by raising the fuel boiling point. Tetraethyl lead was first added to gasoline in the U.S. in the '20s to improve burn and reduce detonation and was phased out of pump gas starting in the '70s for health and environmental reasons. Products like Max Lead 2000 (www.maxlead2000.com), which is genuine tetraethyl lead, boost octane and increase the boiling point by as much as 30 degrees which reduces detonation and improves driveability in engines with 9.5:1 and higher compression ratios. These products cannot be used in cars requiring unleaded fuel or equipped with catalytic converters.
 
Dick S
Would a phenolic spacer like the early T-Birds used be better than the aluminum spacer since the heat transfer is less? The Birds, at least the '56, had a spacer of about 1/4 inch on the four barrel. Anyone making one using this material?
Thanks,
Milt K from Pa
 
I have clothes pins on my 39 Peeekup. When my womens ask what the clothes pins are for, I say "to hang up your shirt with!"
And that is when the fight starts.
Clem
 
Just got my 36 Cabriolet resto almost ready to run-Doubled up on the carb gasket,had Skip work on the coil & added an elec fuel pump for back up/ hope it works ok in Florida heat:) I will keep the spacers in mind if:(
 
I happen to live 3 miles from a circle track and the local gas station sells 110 octane leaded racing gas { UNOCAL } at the pump . This stuff is $5.99 a gal and it doesn't go bad sitting over the winter nor does it boil out of your carb or whatever . Even in the racecars that can get REAL WARM at times it doesn't give any trouble . I put it in stuff that will be sitting over the winter and it cures the spring hard start deal you get with modern crappy gas . I believe it is available in unleaded also but not at this station . I talked with the owner about this gas and he told me that it is really just old style gas made from good stuff with a little more tetraethyl lead in it . If you are going to do a parade on a hot day this stuff will get the job done for you . :D On a different note The good big chev motors from the late sixties { L-88's } had a flat aluminum plate about twice the size of the carb between the carb and intake to help keep the fuel cooler as cooler fuel = more horsepower . Dick is offering something here that should help with vapor lock issues . David J
Roger/Sacramento said:
Read this article

The addition of ethanol, as well as increased oxygenation, and the removal of lead, has lowered the boiling point of pump fuel significantly in the last few decades. Boiling fuel is the cause of vapor lock, a common problem with older carbureted cars. New cars are built to compensate for this change, but older cars weren't.

The fuel boiling point can be raised by pressurizing the fuel, using a high-pressure electric fuel pump located close to the fuel tank.

Lead additives, where legal, can fight the effects of ethanol gas by raising the fuel boiling point. Tetraethyl lead was first added to gasoline in the U.S. in the '20s to improve burn and reduce detonation and was phased out of pump gas starting in the '70s for health and environmental reasons. Products like Max Lead 2000 (www.maxlead2000.com), which is genuine tetraethyl lead, boost octane and increase the boiling point by as much as 30 degrees which reduces detonation and improves driveability in engines with 9.5:1 and higher compression ratios. These products cannot be used in cars requiring unleaded fuel or equipped with catalytic converters.
Click to expand...
 
I am new to the site. I have a 1955 ford country squire wagon. I have a serious vapor lock problem. I have a things about using clothes pins. where would you put them and do they work lol.
thanks
 
During the EFV-8 C/A Grand National Cross Country Tour most of us had issues with vapor lock at one time or another. This happened on just about every FH powered vehicle on this trip from the '32's to the 53's. Most of the time it occurred while climbing the mountains when we stopped our cars for some reason. My '35 fordor has the exact carburetor heat shield that Dick Spadaro shows in his earlier posts. (and the judges at Tahoe did not like it, lol :)) It may have kept the carb fuel cooler but with the glass bowl FP on my car I could see the ethanol boiling in the bowl at engine temps of ~ 190F. This caused enough pressure in the FP and gas lines leading to and from the FP to completely stop the flow of gas. Even when I changed to an earlier style steel top FP, I still had problems with VL. The only quick cure I found was placing towels soaked with ice water on the FP, carburetor, and gas lines. This got me going again in about 5 minutes every time. The problem seems to be compounded using ethanol gas at high elevations on hot days. I have some ideas, thanks to George Mitchell, that I would like to try on my car to reduce or eliminate VL using this ethanol enriched stuff they call gas.

OBTW, I had a Skip Haney wound coil, his rebuilt early style water pumps and his radiator overflow check valve on my '35, all of which worked well to get me across the country and back.
 
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After my Pike's Peak trip when I had to pour water on the fuel pump to get going again every time it vapro locked I installed a backup electric fuel pump back by the gas tank that solved the problem. Every time I get the first hint of vapor lock, either stopped or going, I just switch that pump on until I'm running smooth again then turn it off if I want to or just leave it on if I'm climbing a mountain. That seems to be the most common solution for vapor lock and it makes no changes in the engine compartment to preserve authenticity. Here's my installation:

Fuelpumpelectric.jpg
 
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