Vapor Lock and how to fix it?

[Richard McBurney]

I have a 64 Deville Convertible, keep running into the same problem - vapor lock on hot days. So far I have rebuilt the carburetor , new gas tank , but when it sits in traffic on a hot day it will vapor lock .  It will take about 30 minutes for it to cool down, then starts up and runs again.  My Son said dont drive it on a hot day , think that is ridiculous.

Has anyone else run into this issue?  And does anyone know of any solutions or suggestions? 

Appreciate it 

Rick McBurney

[Tony and Ginny 429]

Sammy 

Pls give us the specific materials and spacer info you used to be solving your vapor lock problem 

This will benefit the people in our community who have that issue as an option 

I used all the stock gaskets and the stock black spacer from the stock Carter carb when installing my 1406 Edelbrock to my 64 - 429 ( old carb off and new bolted in ) 

I did have to block the PVC inlet in the black spacer as the new carb comes with a second one 

I had to go two stages richer on my metering rods and jets with the help of the Edelbrock techs (  very helpful ) as my plugs were burning a whitish color right after installing the carb ( lean fuel mixture ) 

Plugs when the correct color will be  burning a brown paper bag color 

Enjoy 

[Sammy]

I've been searching through all bills I still have from that time.

Haven't found it yet, but I don't give up.

I used completely different spacers from Edelbrock. Not the original ones.

Will search for the correct number this evening. 

But my spark plugs are just a little whiter too.

Which rods and jets did you use?

[Tony and Ginny 429]

All jets and metering rods have numbers on them 

Give the numbers to the Edelbrock techs they will direct you 

Your local auto parts store ( Advanced Auto — etc ) will have your new  jets and metering rods 

I had to go two stages richer with my 64 - 429 when using the Edelbrock 1406 wit elec choke 

Enjoy 

[Sammy]

Here in Germany I don't have a shop that is really into that, so noone I could ask.

Did you call the Edelbrock guys or write them an email? 

[Roland Moser]

i raised the fluel level in the Carter by leveling out the floats a bit higher, to no avail, engine still dies when hot and idling.

i watched the fuel level in the filter and when the engine stalls the level is really low, below the filter:

[Russ Austin]

Replace the fuel pump. 

[Roland Moser]

guess i have to.

but what seems odd to me is the fact, that the car runs perfect when i drive on the highway where the engine needs a lot of fuel!

only when hot and at idle speed the engine runs rough and stalls sometimes.

[Tony and Ginny 429]

 Richard

What is the condition of your engine tune - points - timing and proper idle speed adjustment speed 

The tune parts SB replaced every 6m miles per the service manual 

An out of tune engine ( worn points —dist cap - ign wires ) and a low idle will cause the engine to run hot and stall ( mostly retarded timing the result of worn points ) 

I would be changing the fuel filter and checking the  metal screen fuel filter located in the metal lines going into your carb for debris 

You need to know some  basics are correct as a base line to trouble shoot further 

Enjoy 

[Tony and Ginny 429]

If you change your dist cap - only get one with brass terminals  as any other will get you stranded someplace at some point in the future 

Enjoy 

[Roland Moser]

i installed a Pertronix 3 Ignitor a couple years ago, timing is 6-7 degrees BTDC.

did a full rebuild on the Carter a couple years ago.

car was running fine ever since and it was also hot as hell and had never experienced such problems.

i have a new Carter M3993 Fuel Pump at home that i ordered some time ago as a spare, never did anything on the fuel pump, will change it soon and let you know the result.

hope this Made in China Pump will last longer than others reported in this forum. 

[Mack]

Hi there

Well, I struggled with the same problem for the last few years with my 63 Caddy with AC.

I tried all kinds of tricks: shroud, bigger 7 blade fan blade, rebuilt carb, closed middle port under the intake, heat shield sleeve over the fuel lines, new fuel pump, actually PUMPS! Then I even found a guy who manufactures the heat shields that go under the carb… same s%#t. 

few weeks ago I ripped dash pad out, took the heater core out and … i replaced vacuum lines, heater core, vacuum units, water control valve, 17lbs radiator cap, replaced the thermostat with the 180F,  installed new blower motor etc

the test drive was two weeks ago during parade at Hot August Nights in Reno doing 2mph for 15-20min in the 90-95F weather! 
temp only came up to the half so I let the blower go for a bit which helped to drop the temp a bit.

it works, keeps the temp down and it was what I thought - extend the cooling system to its fullest via heater core which in my case was bypassed. 

therefore, I highly suggest you - do the same! Don’t waste your time and sleep over it like I did.

heater core is not that bad of a job and I am 6’7 and had no problem taking it out from

under the dash, just be patient :)

email me if you’ll need some help or even if you’re around Sacramento or Reno I could give you a hand with it .

[Tony and Ginny 429]

You can always cool the engine down by turning on the heater — if it is running hot and the heater is working 

Depending on  outside conditions it could be less than comfortable for a while but will keep you from overheating the engine 

I have no issues with my 64 convert regarding vapor lock and at the moment my heater core is by passed but I mostly use the car when the temp is in the 80’s  in central Fl and she  does run amazing as is 

Enjoy