Possible Vapor lock hard hot start solution

[G.M.]

John the carb cooling is easy to solve, Just a 1/2" vented phenolic spacer cures that. The heat from the intake manifold heats the fuel pump. A steel intake has a little more clearance then an aluminum one. The aluminum manifolds just about touch the fuel pump. I even tried raising the pump 1", making an insulator between the pump and manifold and even a high speed computer fan above the pump plus insulated fuel line from frame to pump. I tried each of the items by themselves and each improved but did not eliminate the vapor problem. All of the above items pretty much cured it by looks like Rube Goldberg under the hood. Don't forget I have the advantage or disadvantage to having 90 degree weather for months at a time. When testing I go the same route of about 25 miles each way and stop for lunch for 1/2 hour. I carry the laser thermometer and jump out and take readings. Also take them at start of the run, stop and after sitting 1/2 hour. This also gives me the start characteristics. I usually open the hood in real hot weather when I stop this really gets rid of a lot of heat. Some year Fords have less air movement at the rear of the engine where heat builds up and stays longer. The valves in the gauge line are to be able to Watch the pump or needle valve function. The 39 deluxe is about as bad as they get. John give me a call and ride up to Honey Brook some day, I'll buy lunch. G.M.
The fitting with the shut off valve to the right of the gauge was to try a slight fuel bypass line back to the tank. This should solve the vapor problem in the pump but haven't tried it yet.

 

[keith oh]

I have often wondered why Walnut wood seems to be the wood of choice for a heat barrier. It is not really a very hard wood and the grain is not as close as, for instance, Sycamore or Hickory. Maybe the dark color is preferred...

 

[JM 35 Sedan]

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:

Old Henry, the electric fuel pump is certainly one way to help overcome a vapor lock problem. There was a debate about allowing electric fuel pumps on cars being judged at Early Ford V-8 Club meets during this years Golden Jubilee GNM at Lake Tahoe. Many feel this vapor lock situation can be a driving safety issue and I agree with that thinking based on some personal experiences that I had on the Cross Country Tour. Apparently the EFV-8C/A is not willing to make this change to their judging standards, so for that reason many members will not install electric fuel pumps on their cars. I personally don't worry about that with my cars since they are not or never will be high point show cars. I plan to make whatever changes I can to prevent vapor lock and may wind up installing an electric back up pump as well. This ethanol gas problem will probably get worse if higher %'s of alcohol are allowed.

 

[Bluebell]

Dick, If it works as an insulator, then I think it would be the biggest single thing a bloke can do to minimize the risk.
Most of the high temp heat would surely be transferred through the manifold to the carb.
A good thing Dick.

 

[Roger/Sacramento]

I used walnut because that is what I had laying around.

 

[1952henry]

I removed a carburetor from a flathead Willys engine powering a Hobart welder (factory job). It had a spacer/shield like Dick's under the carb. The engines in Jeeps don't have that shield to my knowledge. I think Dick's got something there.

 

[JM 35 Sedan]

John give me a call and ride up to Honey Brook some day, I'll buy lunch. G.M.

George, will plan to do that sometime in August.
I would like to get some of these vapor lock eliminating ideas installed on my '35 sedan and drive it up to let you see them. The glass bowl fuel pump and gas line attached to FP seem to be the biggest area of opportunity. The heat shield between carburetor and intake manifold is definitely helping to keep the carb and gas within the carb cooler.

 

[Blu Dice]

My car doesn't VL very offen just when I put in some cheap gas on a very hot day - if I use Shell it usually runs ok because our Shell gas has a lot less BS in it. But it does VL ts is what I do: I keep in the car a 4" x 4" piece of very hard 1/16" thick rubber, and a 4" x 4" piece of 1/2" steel plate. I take off the air clearer and place the rubber over the opening with the steel plate on top of it - start the engine and it runs every time. Now I know what you are going to say - same can be done with your hand, but it's not true - I don't know why, but it just doesn't happen. Any thoughts on this?

 

[Old Henry]

My car doesn't VL very offen just when I put in some cheap gas on a very hot day - if I use Shell it usually runs ok because our Shell gas has a lot less BS in it. But it does VL ts is what I do: I keep in the car a 4" x 4" piece of very hard 1/16" thick rubber, and a 4" x 4" piece of 1/2" steel plate. I take off the air clearer and place the rubber over the opening with the steel plate on top of it - start the engine and it runs every time. Now I know what you are going to say - same can be done with your hand, but it's not true - I don't know why, but it just doesn't happen. Any thoughts on this?

Keeping a gallon of water in the trunk to pour on the fuel pump to cool it down seems a little easier to me if you don't want to install a backup electric fuel pump.

 

[G.M.]

John give me a call and ride up to Honey Brook some day, I'll buy lunch. G.M.

George, will plan to do that sometime in August.
I would like to get some of these vapor lock eliminating ideas installed on my '35 sedan and drive it up to let you see them. The glass bowl fuel pump and gas line attached to FP seem to be the biggest area of opportunity. The heat shield between carburetor and intake manifold is definitely helping to keep the carb and gas within the carb cooler.

John I was thinking about you a while ago when I got bite by the carbonized 110 plug on my work light. It got me 3 times this morning while doing an engine swap in my 78 GMC diesel P/U. I stopped and cut the soft yellow plastic material around the prongs and on the sides to get rid of the carbon. Plugged it in and felt the area, no more shock. . G.M.

 

[Blu Dice]

Keeping a gallon of water in the trunk to pour on the fuel pump to cool it down seems a little easier to me if you don't want to install a backup electric fuel pump.

I've already installed a electric fuel pump - but as I said before as long as I use Shell gas and MMO I don't seem to have a problem with VL.

 

[Bluebell]

I removed a carburetor from a flathead Willys engine powering a Hobart welder (factory job). It had a spacer/shield like Dick's under the carb. The engines in Jeeps don't have that shield to my knowledge. I think Dick's got something there.

1952 Henry. Yes the wartime Jeeps (Ford and Willys) has a 1/4" thick insulator that had a v shaped "atomiser" hanging in the middle of the manifold inlet.

 

[joe 1950]

I agree with andy my 1950 ford and my friends 1940 ford had the same problem with the hose from the main line to the pump it would suck together after getting hot replaced the hose with a good piece of gates fuel hose and quit using the corn squeezings gas and all is well in green bay wi.

 

[1952henry]

1952 Henry. Yes the wartime Jeeps (Ford and Willys) has a 1/4" thick insulator that had a v shaped "atomiser" hanging in the middle of the manifold inlet.

True, but I am talking about a thin sheet metal shield that goes between the carb and manifold. It is roughly 3X4" and is what Dick is describing. You're referring to the gasket with diffuser.