When I drive my 63 after about a hour it will shut of and the gas bowl will be somewhat empty and the car will not start until cools down. I have changed the fuel pump and remove the Thermostat. Changed the coil and condenser. I have asked around and people tell me so much things that my head is spinning. They said my gas may be vaporizing or it may be electrical or something in the tank. Any suggestion. I left a message AAron JHONSTON and TONY AND GINN 429 I sent you guys messages in your inbox for you guys could contact me I saw you guys commenting on this earlier or you guys could call me at 786-314-1360 I would truly appreciate it

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Comment by Tony and Ginny 429 on July 18, 2013 at 10:09pm
Looks like slowly we are getting to the bottom of James and Aaron's difficult problem to diagnose
As the problem is unique to the 63-64 engines intake manifold design
James feed back should help confirm the issue they may both be having
Comment by Aaron Johnston on July 18, 2013 at 8:32pm
I called him today to tell him what was going on with mine, sounded like he may be having the same problems? Advised him to pull the intake for inspection
Comment by Tony and Ginny 429 on July 18, 2013 at 3:13pm


If you are watching this site ,you will see that one of the people on here has just found a tube in his intake manifold broken ( the choke tube ), causing his intake manifold to get very hot ,and preventing his carb from working as it should, as the tube is a direct connection to the very hot exhaust gases in the exhaust manifold

This heat build up will evaporate the gas in the carb ,once it gets hot enough

A strong possibility you are having the same issue ,as your cars carb  will take about a half hour to get hot enough ,and cause the car to stop running as it should, until the carb gets a chance to cool down again, hold fuel as it should ,and start again

The 390 and 429 motors hold heat for very long periods of time before they will cool down ,unlike many other cars made,which adds to the problem you are having regardng getting it started again

If the car stops after a half hour again , do what you can to see if your intake manifold is very very hot ,that would be a good clue

Do not burn yourself, could be 4-500 degrees, as it is 3-350 degrees when working correctly

This item gives many here problems as the cars are old ,and this  design does not hold up in many cases due to age and wear

Comment by Jason Edge on July 13, 2013 at 5:39pm

Tony could be on to something about the heat riser. Aaron, had posted about their intake heating up to 500 degrees and vaporizing the gas. He was going to check the heatriser and get back with us but never did (I will reply on that thread also)..

Anyway, check to make sure it is opening up. If it is stuck closed almost ALL Left/driver side fire hot exhaust gas will continue to push across the intake causing the intake to over heat.

Here is a link to a picture showing the heat riser open and some discussion below:


Here is the other message thread from Aaron:


Comment by Tony and Ginny 429 on July 13, 2013 at 4:01pm
Feels like something is heating up and stopping the car after the half hour interval
Do you know if you have the correct gaskets and the spacer under your carb ,that s/b there depending on the carb you have
If the issue was fuel only the car would not run for the half hour interval ,over and over as it is
Comment by Tony and Ginny 429 on July 13, 2013 at 3:48pm
Could this be a stuck closedv exhaust heat riser , getting the carb so warm the fuel is evaporating ?
This was just suggested a short time ago on another post --I think
Comment by Tony and Ginny 429 on July 13, 2013 at 3:27pm
Do not disregard the fellow in the last post that said ,he had the problem and it was more a ground strap problem for him, that he solved
Comment by Russ Austin on July 13, 2013 at 1:41pm

The empty fuel bolw is the sign of fuel problems. As listed above, start at the gas tank.   Change the sending unit filter, clean out the tank, and make sure the vent tube is not blocked.  Change all the rubber fuel lines.

Flush out the main fuel line(s) with compressed air.

The new fuel pumps comming out are getting a bad rep for the rubber diaphrams going bad quickly.

If after you do all that, and it still stalls, replace the fuel pump again, as its whats bad.  I am in the process of installing an electric fuel pump. I'm tired of playing the fuel pump game.  

Comment by Jason Edge on July 13, 2013 at 6:05am

Just a tip on the website, if you click on someone's name it shows their last few posts, replies, etc. The Ning site is much more interactive and intuitive than the old MSN and Yahoo sites. I'm still finding features where I say to myself "Cool!".  I clicked on James' name and "latest activity" showed this post, the previous "wiring" post, and the 'Car Trouble" post.  I actually use it to find stuff I've posted myself all the time! LOL 

Also, as a general note, typed words can sometimes seem cold and harsh. I know I'm probably more guilty of this than anyone, but  we are all here to help each other. I get tons of praise for the incredible amount of support 63 & 64 owners get at our site, so do appreciate everyone keeping everything civil and encourage everyone to learn more about these cars in a positive helpful manner.

Comment by David Thomas on July 12, 2013 at 4:12pm

James, I don't remember your original post as Tony refers to, so I don't know what has been suggested so far.

From your description in this post, I would drain the fuel tank and drop it from the car for inspection to see if it is full of rust scale or dirt. Pull the sending unit from the top and inspect the pick up tube and filter to be sure they are clear and serviceable, it wouldn't hurt to replace the filter while you have it out.

Before you pull the tank, if you can, rig a 5 gallon can of fuel safely in the car, run a pick up tube from the fuel pump to it. Take the car for a drive to see if the symptom repeats itself. If it does not, your problem is in the fuel line to the tank or debris in the tank. One other possibility would be a clogged tank vent. You can check this by crawling under the rear drivers side of the car to inspect the vent tube at the front of the tank. Put a piece of hose over the vent tube and blow air into the tank to see if it is open. If it is not open your fuel pump will eventually draw a vacuum on the tank and fuel will not flow. Another way to check this would be to remove the gas cap when the engine stalls. If you hear a rush of air entering the tank, the vent is stopped up.

HTH, David


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