1956 312 teapot engine dies

[MRansom]

1956 dies when driving. Carburetor rebuilt less than 500 miles ago, changed filter, cleaned carburetor, & added Sea Foam to fuel tank.
when accerating car will die & re-start immediately when accelerator pumped or will re-start immediately when shifted to neutral & starter engaged.
fuel hose?

 

[Ward 57]

1956 dies when driving. Carburetor rebuilt less than 500 miles ago, changed filter, cleaned carburetor, & added Sea Foam to fuel tank.
when accerating car will die & re-start immediately when accelerator pumped or will re-start immediately when shifted to neutral & starter engaged.
fuel hose?

I would look at ignition issues. I had a coil resistor act like that. It would just die even in my driveway but start right back up. It was an aftermarket unit and the ceramic had cracked and the resistor coil was making intermittent contact. replaced it with a correct new one and my problem went away.

 

[MRansom]

I would look at ignition issues. I had a coil resistor act like that. It would just die even in my driveway but start right back up. It was an aftermarket unit and the ceramic had cracked and the resistor coil was making intermittent contact. replaced it with a correct new one and my problem went away.

I believe mine is Mallory, may be hard to identify? Not sure how to test, but thanks for advise

 

[Ward 57]

I believe mine is Mallory, may be hard to identify? Not sure how to test, but thanks for advise

A simple continuity or test light would do it. Just turn the ignition on and touch the contacts to both ends and wiggle the contacts on the resistor and see if the current is constant.

 

[sre]

If the resistor appears OK I would check at what RPM the engine shuts off. If it is close to the same when it shuts down,get coil checked or maybe borrow one you know is good. More then once I have had defective coils. check wiring of ignition circuit.

 

[MRansom]

A simple continuity or test light would do it. Just turn the ignition on and touch the contacts to both ends and wiggle the contacts on the resistor and see if the current is constant.

I see a black wire & a green wire to coul, unsure about ”wiggle the contacts on resistor”?

 

[CSPIDY]

You say you seafoamed the gas tank
Did you check the fuel tank for rust
If there is rust in the tank
It would contaminate the carb
Fine rust particles can get past the filter

 

[zeroroadkill]

1956 dies when driving. Carburetor rebuilt less than 500 miles ago, changed filter, cleaned carburetor, & added Sea Foam to fuel tank.
when accerating car will die & re-start immediately when accelerator pumped or will re-start immediately when shifted to neutral & starter engaged.
fuel hose?

Sounds like a fuel delivery problem to me.
Are you using the original fuel pump? Most replacement pumps are junk. Pumping the throttle ( accelerator pump) you are getting a boost of fuel to the intake. So I’d check the fuel delivery system and the float level to insure it’s allowing maximum flow. Just a thought! Also pop the fuel tank cap to see if there is a vacuum, not sure on a 56 but a 55 the tank is not vented which required modifying the gas cap to allow air in the tank to counteract the vacuum caused by sucking gas out of the tank. If I’m correct the 56 has a vented gas tank??? Might want to check to see if it’s plugged up. Could be vapor lock check your fuel lines around the engine and make sure they’re not touching any manifold and also check the gasket under the carburetor to ensure you’re not getting excessive heat from the intake manifold. I’ve installed a thicker fiber gasket under the carburetor to help alleviate engine heat from overheating the carburetor. Just a thought.

 

[Jeff55]

I had the same problem, only less frequent. Mine ('55-292) would die after about 4-5 miles, sometimes longer. I replaced the coil and resistor thinking it might have an expansion short - no go. I insulated the fuel line thinking it might be vapor lock - no go. Then I replaced the fuel pump with one from CASCO - bingo. Looking good so far.

 

[paul5456]

Possible junk in the gas tank. The junk may be sucked into the outlet (maybe too big to get through) thereby shutting off the gas. When the car stalls, the junk falls back, allowing gas to flow until it again gets sucked into the outlet when car is started

it also sounds like classic ignition problem, either coil, resistor or distributor condenser failing when it gets hot..

Another possible cause - A gas cap that isn't vented. All small Birds require a vented cap. If not vented, suction is cut off resulting in no fuel. Next time it stalls, go to the gas cap and take it off. If you get a swooosh when opened, the cap is not vented

 

[doug7740]

Below is an article I wrote on how to correct a gas cap that will not vent on a 1955/56 Thunderbird.

Bellow is a Tech Tip that I wrote about the fuel tank venting on a 1955/ 1956 Thunderbird.
Gas Cap Tech Tip: The gas cap on your T-Bird must be vented to allow air to enter the tank. If air cannot get into the tank vacuum will be created which can stop the flow of fuel to your engine. Last summer, I had to replace my gas cap and I discovered that when I removed the gas cap after running the engine for a while, I could hear the sound of air rushing into the tank. To vent the fuel tank, the 1955 and 1956 gas caps have a rib stamped into the surface which allows air to enter from the outside edge of the cap to the center. The problem with my gas cap was that the inside diameter of the gasket was so small that it prevented the venting process. The problem was easily fixed by removing the gasket from the gas cap and increasing the inside diameter of the gasket by cutting it with a razor blade. Removing just a little bit of the gasket from the inside diameter corrected my venting problem.


doug7740
1955 Thunderbird Blue