I have a 1956 Buick Special. 322 Nailhead/Dynoflow Tran. I have replaced the cap, rotor, wires, and plugs. I have set the timeing and have cleaned the fuel filter and rebuilt the fuel pump. Here is the problem. While driving for a long time, ie more then 20 minutes. I noticed my car starts to lose power, almost to the point that it is sputtering and surging when i give gas. It finally will stall and once i let it sit for while will start right back up, go down the road for a mile, and repeat the symptom. The nest day the car is running like a top again untill i hit the 20-30 minute mark then boom....no power again. Any help would be great.
Does the weather seem to have anything to do with it. Damp, rainy weather could mean carb icing while vapor lock is a possibility in hot weather.
Dave, How would i diagnose vapor lock? is there something i can look for? I live in Florida so its always HOT. LOL Thanks for the Coil Idea, all though it looks quite good, i might as well buy a new one, just in case.
Next time this happens, try taking off the gas cap and see if it starts again. I had that happen once; the return line to the gas tank was plugged. When I drove long enough, the vacuum created in the tank was too much for the fuel pump to overcome.
car dies either it is vapour lock or fuel pump . suggest that u disconnect the fuel line from the fuel pump , remove the gas cap and blow compressed air back thru the line to the tank . then let the gas drain back to the pump into a can before reconnectinthe gas line to the pump . i would guess that there is no gas return line to the tank . i have seen guys , years ago in the old cars , drill a small hole thru the gas cap to let the tank breathe . also , check that the fuel lines, metal or rubber , are not too close to the exhaust manifold which could cause the fuel to boil / vaporize .
56 buick Next time it does it, pull a wire and see if you have spark. If yes, use starting fluid or gas (be careful!) down the carb and see if it tries to start. That will narrow it down to fuel or spark. Usually cars that vapor lock always do it.... is this something new and did you change anything before it started doing this?? - Bill
I had a simmilar problem with my 55 special. it turned out that the ballast resistor was no good. It would runwell for about 30-40 minutes then start sputtering and finally died. After two afternoons replacing plugs, wires, cap, rotor, pooints, condensor, and fuel filter I tried a ballast resistor and suddenly the car ran well again. Strange scenario but it happened twice. THe second time it only took about ten minutes to narrow it down. You would still need to determine if it is a fuel or ignition problem as stated earlier in this post, but don't over look anything. Goof luck!:TU:
I would go with the idea that you determine if it's fuel or spark first. Then you know what to look for. If it's spark next time it fails: try a jumper from each side of the balist resistor and if it runs thats the problem. Next try a new condenser, it's the cheepest item to change, then the coil.
Whoah whoah whoah there I think we are getting alittle to technical with this problem. It could be the resistor or the coil temp, but Id put money it isnt. First off, has the car ever been sitting for quite some time? I would put money on it that its fuel starvation. Lets do it easily. Take a ride out to the auto parts store and get a can of Spray Start. This will be the best $5 investment of your life. The car dies, you get out, and spray the stuff down the carb neck (with throttle open) Get back in, turn the key, and if it starts, its a fuel problem. If not, its spark. If its spark, go through the 5 or so components that generate spark, and you should find your answer. A friend of mine is going through this with his 56, I did with my Merc and I am heading it off at the pass with my 55 Olds. The only way to really remedy this problem...drop the tank and have it boiled and coated (most radiator shops will do it). Then we replace the fuel line, or flush it out if you're really lazy. Next replace or clean out fuel pump, add two new filters (pref clear Spectre types) with one before the fuel pump and one between fuel pump and carb. Clean the carb out with some 2+2 carb cleaner, and Im sure you will be on your way to many trouble free miles. I have not come across a car thats been sitting for years that has not had MAJOR fuel problems down the road and left me stranded. Cut it off at the pass if its fuel, spend 200 bucks or so, and be straight for good. PS...if you are really broke like me, try using Coca Cola (approx 8 liters at a time in an empty, dry tank) Pour it, shake it around, let it sit overnite. Repeat this a few nites and finally wash it out with water (high pressure) and let it dry. Not nearly as foolproof as the radiator shop method, but it only costs about 10 bucks. Chris
