1968 carburetor help

[AshtonR2003]

I am 18 years old and I recently went off and bought a 1968 T-Bird with a 429, it’s completely original and the interior is prestine while the exterior is a solid 6/10. I bought the car and drove it home 2 hours with no issues, then today I went to drive it and it died at the stop light and it sputtered as if it was out of gas. So I pushed it to a pump as I conveniently died right next to a pump and put 10 in. I got back home and realized I had a full tank as it was overflowing with gas and wondered what it was that could possibly be causing that, it only happens when it gets hot but when cold it will drive perfect, the carb is also spitting out some fuel out of the lever pump on top of the carb but I’ve only owned older GM Vehicles and I have never seen that type of mechanism before and know little about how it works. Any help on that would be very appreciated as I can’t find any info on what could be causing the gas to surge out of the carb in that little area. The second question I had was what type of octane gas should I be running? I can’t find info on my exact model anywhere or what type of octane would be safe to run as I live in a “smaller” town in Oklahoma and the max octane most places around here is 89

 

[Toothaker]

First off, congratulations on your new Thunderbird.

The carburetor probably needs to be rebuilt. There are kits available, and simple tools are needed. Usually the instructions that come with the kit are good, and searching out more details ahead of installing the kit is a good idea.

A carburetor is all mechanical. There are floats, much like the one in a toilet, that meters the gas as it enters and fills the fuel bowl. If it gets clogged with debris from the tank it will overflow from the fuel pump pressure.

You are going to learn a lot about older technology.

 

[FishEpperson]

If it has the original ford autolite carburetor they are junk, they were designed by quadra jet. My 67 had one, I replaced it with a Holley 600 and it made a big difference. as far as the gas running out when it's full, check the rubber gasket where the filler tube goes in the tank. Mine started leaking a few weeks ago, only when I filled it up and it was the rubber gasket. Mine was original, ebay was like $50. I live in Arkansas in a small town and run 87 or 89 octane with no ethanol.

 

[biddle]

. The second question I had was what type of octane gas should I be running? I can’t find info on my exact model anywhere or what type of octane would be safe to run as I live in a “smaller” town in Oklahoma and the max octane most places around here is 89

Use ethanol free gasoline. Locate a station selling it here- https://www.pure-gas.org/

 

[lagzilla_86]

Toothaker beat me to the comment: The Carb is probably "Crudded Up" and needs a cleaning or rebuild if especially clogged and permenantly affected. Great Car and the engine is a fantastic piece of work by Ford.

 

[Toothaker]

If it has the original ford autolite carburetor they are junk, they were designed by quadra jet. My 67 had one, I replaced it with a Holley 600 and it made a big difference. as far as the gas running out when it's full, check the rubber gasket where the filler tube goes in the tank. Mine started leaking a few weeks ago, only when I filled it up and it was the rubber gasket. Mine was original, ebay was like $50. I live in Arkansas in a small town and run 87 or 89 octane with no ethanol.

Agreed! The Autolite carb is junk. I was thinking that an 18 year old would be on a budget. Plus, installing a Holley will mean tweaking the linkages and fuel line. Buying a used carb will also mean rebuilding it, too. So I was focused on getting him back on the road. But yes, a Holley or even an Edelbrock like I run will be a good, long term solution.

 

[AshtonR2003]

If it has the original ford autolite carburetor they are junk, they were designed by quadra jet. My 67 had one, I replaced it with a Holley 600 and it made a big difference. as far as the gas running out when it's full, check the rubber gasket where the filler tube goes in the tank. Mine started leaking a few weeks ago, only when I filled it up and it was the rubber gasket. Mine was original, ebay was like $50. I live in Arkansas in a small town and run 87 or 89 octane with no ethanol.

It is the original carb, the car is completely original only 59k original miles

 

[FishEpperson]

It is the original carb, the car is completely original only 59k original miles

Congratulations. It is nice to see young people still interested in old cars

 

[64ZCODE]

I am 18 years old and I recently went off and bought a 1968 T-Bird with a 429, it’s completely original and the interior is prestine while the exterior is a solid 6/10. I bought the car and drove it home 2 hours with no issues, then today I went to drive it and it died at the stop light and it sputtered as if it was out of gas. So I pushed it to a pump as I conveniently died right next to a pump and put 10 in. I got back home and realized I had a full tank as it was overflowing with gas and wondered what it was that could possibly be causing that, it only happens when it gets hot but when cold it will drive perfect, the carb is also spitting out some fuel out of the lever pump on top of the carb but I’ve only owned older GM Vehicles and I have never seen that type of mechanism before and know little about how it works. Any help on that would be very appreciated as I can’t find any info on what could be causing the gas to surge out of the carb in that little area. The second question I had was what type of octane gas should I be running? I can’t find info on my exact model anywhere or what type of octane would be safe to run as I live in a “smaller” town in Oklahoma and the max octane most places around here is 89

Besides the possible carb rebuild/replacement, your fuel pump may be failing intermittently. This is an inexpensive part and easy to replace for avoidance of doubt.

 

[AshtonR2003]

If it has the original ford autolite carburetor they are junk, they were designed by quadra jet. My 67 had one, I replaced it with a Holley 600 and it made a big difference. as far as the gas running out when it's full, check the rubber gasket where the filler tube goes in the tank. Mine started leaking a few weeks ago, only when I filled it up and it was the rubber gasket. Mine was original, ebay was like $50. I live in Arkansas in a small town and run 87 or 89 octane with no ethanol.

Also was the gas spitting out causing it to sputter and shut off??

If it has the original ford autolite carburetor they are junk, they were designed by quadra jet. My 67 had one, I replaced it with a Holley 600 and it made a big difference. as far as the gas running out when it's full, check the rubber gasket where the filler tube goes in the tank. Mine started leaking a few weeks ago, only when I filled it up and it was the rubber gasket. Mine was original, ebay was like $50. I live in Arkansas in a small town and run 87 or 89 octane with no ethanol.

If it has the original ford autolite carburetor they are junk, they were designed by quadra jet. My 67 had one, I replaced it with a Holley 600 and it made a big difference. as far as the gas running out when it's full, check the rubber gasket where the filler tube goes in the tank. Mine started leaking a few weeks ago, only when I filled it up and it was the rubber gasket. Mine was original, ebay was like $50. I live in Arkansas in a small town and run 87 or 89 octane with no

 

[OneAmongOthers]

I would also recommend upgrading to a Pertronix ignition and get rid of the old points system in the distributor. Much, much more reliable and less headache to worry about. Also relativity inexpensive as well. As for the carburetor... floats getting stuck is a common problem. You can also try spraying some Gumout or carb and choke cleaner in there and see if it helps it getting the sticky gunk out of it. Replacing the fuel pump is a bit of a chore on these cars as its on the left side of the engine right behind the power steering pump and lower radiator hose. When was softer valve seats an issue? Wouldn't lower octane fuel cause problems?

 

[AshtonR2003]

I haven’t had time but I’ll definitely clean it out today, thank you for the advice