Classic/Antique Car Repair: 66 mustang, steel line, needle valve


Question
my 66 mustang will be running one minute then sputtering and dying the next. if i try giving it gas it will sometimes sputter back on but it wont stay on. when i open my hood it smells like gas so ive started to think that it might be fuel related...but have no experience to know for sure. its a straight 6 and everything under the hood seems to be fine. please help!!! i have to get to school and work! thank you in advance.
katelyn

Answer
The gas smell is a serious problem, because you would not be able to smell it unless there was liquid gas under the hood. There could be a dangerous condition, and you probably should have a professional look at it for you.  If you want to do some troubleshooting yourself, do the following:   

Push the car out of the garage so that if there is an engine fire, you won't lose the house!

Take the air cleaner off the top of the carburetor, and see if you can see any liquid gasoline with the car not running. Check around the carburetor, especially the top and down inside the front opening of the carburetor.  Check the steel line that comes into the carburtor from the fuel pump, to see if there is any leak there.

If you see no liquid gas, try starting the engine with the hood open, and even if it doesn't start, just crank it with the starter for about 10 seconds, then turn off the key and look again.  The gas smell should be stronger, and maybe you can spot the cause now.  

Regardless of how you find the leak, if it is leaking down inside the top of the carburetor, it is probably a stuck needle valve in the carburetor, which you may be able to  temporarily jar loose by rapping on the fuel line where it enters the carburetor with the handle of a large screwdriver or the like - don't hit it with anything metal - you don't want to make a spark and you don't want to damage anything. Even if you manage to make it run OK again, it is going to keep doing this, and the only cure is to replace or rebuild the carburetor. If you want to, you can rebuild it yourself, all it takes is the correct kit (available at the auto parts store, normal hand tools, the ability to read and follow directions, and a well lit clean place to work, plus a can of spray type carburetor cleaner (Gunk is a good brand).  You will probably also have some gasoline mixed into the engine oil - so check your dipstick for gas odor, and if you note any, do not run the car that way - drain and change the oil and filter before running it again - you could have a nasty explosion from gas fumes in the oil.   

If the leak is somewhere else, such as on the outside of the carburetor, or in the fuel line from the fuel pump to the carburetor, you MUST cure that problem before continuing to troubleshoot any other problems with the car.

If you want further instructions after you've done the above, post a follow up question and I'll try to help further.

Be careful - this could be a dangerous situation!  Wear eye protection, and have a fire extinquisher rated for gasoline fires handy while you work on it!

Dick