Possible Vapor lock hard hot start solution

[DICK SPADARO]

I ran across this item the other day, it is a new product to help dissipate the heat from the engine to the carburetor and eliminate the vapor lock or hard starting issues involving the new ethanol based fuels vaporizing.

These aluminum plastic laminate spacers go between the intake and the carb base to slow the heat transfer to the carb body and help cut down on the fuel percolation during high temperature operation.

I have been fooling with this all day and did a simple non scientific test to determine the if indeed the spacer does cut down on the thermal transfer and help the carbs run cooler.

Simple experimentation was with a heat gun and two thermometers on each side of the spacer plate. Attempting to regulate the heat from the heat gun was done to simulate engine operating temperature and at a 170* starting point. The temperature when normalized seemed to hold on the top side around 120* or a 50* difference keeping the heat from the carb and the additional size of the deflector keeping the heat away from the float bowl.. They are available in just a spacer or as a spacer floatbowl deflector unit.

I'll have them at the NE V8 club meet, Carlisle and following events for you to check out or you can call if you are interested. Both kits come with two mounting gaskets. If time permits I'll answer any questions on the Barn for those interested.

Anyway I thought this would be for interest since its getting to be driving season again in most of the real world.

[donald1950]

do they make them configured for the holly 390 cfm 4BBL carbs ?

don

[uncle max]

Every 9super7 needs a set of spats!

[FRANK PKNY]

Does vapor lock also happen in the fule line? I have duals on my pickup and the fuel line runs kinda close around the firewall area. I did have a vapor lock problem one time, so I insulated the fuel line with some aluminum foil type material. So far it has worked, but I have not driven it in very hot conditions. Frank pkny

[flatjack9]

Originally Posted by donald1950

do they make them configured for the holly 390 cfm 4BBL carbs ?

don

In 18 years I have never had a heat related problem with my 390 Holley.

[4dFord/SC]

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Originally Posted by donald1950

do they make them configured for the holly 390 cfm 4BBL carbs ?

don

Speedway sells phenolic spacers for Holley 4bbls.

[4dFord/SC]

Originally Posted by 4dFord/SC

Speedway sells phenolic spacers for Holley 4bbls.

Adding to Flatjack's comment, the only hard starting problem I've experienced with my Holley 390 was caused by a leaky power valve.

[oldford2]

My two cents worth- I think Skip Haney's coil rebuilds have cured more "vapor lock" than clothes pins on the fuel line and all the other remedies. John

[GaryTx]

Originally Posted by oldford2

My two cents worth- I think Skip Haney's coil rebuilds have cured more "vapor lock" than clothes pins on the fuel line and all the other remedies. John

I agree...Once I had skip rebuild my coil it cured all the heat related starting problems...

[Enbloc]

Originally Posted by oldford2

My two cents worth- I think Skip Haney's coil rebuilds have cured more "vapor lock" than clothes pins on the fuel line and all the other remedies. John

I was just thinking the same thing!

I bet 99.9% of "vapour lock" problems are ignition related.

[Andy]

My experience faults the rubber hose from the fuel line to the pump. If that hose will not hold a vacumn, you are done. They look fine on the outside but maybe not so fine on the inside.

[JerseyJim]

Every time the subject of vapor lock comes up, I'm always surprised at the number of people who consider it to be an urban myth of some sort. Ethanol blending has definitely made vapor lock more of an issue. Chevron says that ethanol is not the oxygenate of choice especially in the summer months when the window for avoiding vapor lock is considerably narrower. The refineries do the best they can but ethanol blended fuel reduces protection against vapor lock and cars like ours are more sensitive to the problem. Newer fuel injected and highly pressurized systems are more tolerant.

I have an Econoline pickup. An engine in a box can get pretty hot. The first tank of ethanol blended gas wreaked havoc on that truck. Sitting at a traffic light would boil off the gas. The first time it happened, I looked down into the carburetor as I cranked it and could see that I was getting no gas. I removed the fuel bowl and it was dry as a bone. I cranked the engine with the fuel line removed until gas began to flow into a can. Reconnected the line and drove the truck home.

I took a number of steps to make sure that I avoided the problem in the future. I made a phenolic spacer for the carburetor, replaced my four blade fan with a six blade fan, and also improved the insulation on my fuel lines. Three years now and so far so good. Still worries me when I sit in traffic though.

[Gary in La.]

I've had a pair of these "genuine FORD vapor lock clothes pins" on my fuel line for 20 years and have'nt had vapor lock one time.

[FL&WVMIKE]

Originally Posted by DICK SPADARO

I ran across this item the other day, it is a new product to help dissipate the heat from the engine to the carburetor and eliminate the vapor lock or hard starting issues involving the new ethanol based fuels vaporizing.

These aluminum plastic laminate spacers go between the intake and the carb base to slow the heat transfer to the carb body and help cut down on the fuel percolation during high temperature operation.

I have been fooling with this all day and did a simple non scientific test to determine the if indeed the spacer does cut down on the thermal transfer and help the carbs run cooler.

Simple experimentation was with a heat gun and two thermometers on each side of the spacer plate. Attempting to regulate the heat from the heat gun was done to simulate engine operating temperature and at a 170* starting point. The temperature when normalized seemed to hold on the top side around 120* or a 50* difference keeping the heat from the carb and the additional size of the deflector keeping the heat away from the float bowl.. They are available in just a spacer or as a spacer floatbowl deflector unit.

I'll have them at the NE V8 club meet, Carlisle and following events for you to check out or you can call if you are interested. Both kits come with two mounting gaskets. If time permits I'll answer any questions on the Barn for those interested.

Anyway I thought this would be for interest since its getting to be driving season again in most of the real world.

DICK SPARADO ......................
Your heat shield might be perfect for blocking heat from a heat gun. But, You did not include the factor of air rushing in, through the engine compartment.
I believe "vapor locks" do happen, but I also think that most "vapor locks" are caused by the coil.
MIKE

[Roger/Sacramento]

I thought it would be cute to make up walnut wood spacers. That along with two gaskets should be good insulation. Look at the enclosed picture.

[Django]

I would be interested to see if the 50° difference holds on a car in use.

That clothes pin is seriously a Ford piece?

[Gary in La.]

No,it's not really a Ford part. But I do have them on the car and in all these years it has been a sure fire conversation starter. It has been amazing how many older Ford guys have heard of it as a cure. I just do my part in keeping the myth going.

[FlatheadTed]

Gary did Skip set up your distributor to ?

Originally Posted by GaryTx

I agree...Once I had skip rebuild my coil it cured all the heat related starting problems...

[G.M.]

Teds if Skip did set up his distributor it was done on a Ford~Heyer strobe machine to the original ford factory specs. Skip has several of these machines and both set exactly the same off the master distributor he keeps in a plastic bag and checks the machines once in a while to make sure they stay set. My distributors were done on his machine and they run perfect at all speeds up to 90 MPH. I drive at 65 to 75 for 8 or 10 hours and never get the slightest miss. G.M.

[DICK SPADARO]

Since I posted this it has been interesting to see the various post show up regarding experiences with vapor lock and the solutions. To those that have not had the experience of overheated fuels, it is a thrill when you least expect it. If you intend to use your car in the "new world order" be ready for vapor lock with these newly formulated ethanol based fuels in vehicles that were designed for suction feed carburetors.

It was interesting to see that a number of you thought vapor lock was an ignition related issue when it isnt. Fuel is fuel and spark is spark, the solution of rebuilt coils as a cure for hard hot starting only remedied the fact that the higher operating temperature of the original coil increased the internal resistance and diminished the efficency of the coil and therefore cut down the intensity of the spark. Replacing the coil with a Haney rebuild was fine but most likey that coil has a different size wire combination that builds up less resistance under temp and therefore has a better spark. This fires the fuel mixture easier, with out a comparison you may have achieved the same results by just using a new version barrel coil or even checking the ignition electrical grounds for a better contact.

Back to the vapor lock issue with the clothes pin, I will say I have tried it and it actually acts as a heat sink on the fuel line. The ears of the clothes pin act like cooling fins of a radiator and as the increased temperature warms the fuel line the air flow around the clip help cut down the heat transfer, its a great conversation piece.

The real issue that has to be addressed is the fuel percolation issue with the new fuels we are now subject to and how to overcome this in a vehicle that uses antique technology. This spacer may be a cure or just a stop gap measure, however if you intend to use you vehicle in higher temperture environments like parades or extended higher temp day cruising you will have to address the fuel percolation or be watching from the side of the road.

Fl Mike had a question about the radiator air flow and the disparity of temps. My take on this is that the heated air temperature from the radiator is cooler than the hotter radiated heat from the engine. So if you shield the carb from the increasing radiated engine heat there will be less chance of the fuel to boil.

The fuel percolation problem has to be carefully examined as even an exhaust pipe or muffler too close to a fuel line will generate enough heat to boil the fuel and create an air bubble that shuts down the fuel flow until the vapor cools and condenses again.

Anyway this is just for converstion, speculation and hopefully avoid a summer breakdown..