QuestionHey Jim, I have the 79 spit that you helped earlier. I have replaced the coil with a 6 volt coil, and the points are good, the car will drive and accelerate just fine for a while, but then it dies without warning. Everything just stops. It does not spudder or anything. The car is all original with the water cooled choke. I have not done anything to the carb. While I am driving about 50mph and it just stops, I can pump the gas and it fires up while I am still driving. Can you point me in the right direction?
Thank you, Jarod
AnswerHi Jarod,
I'm not Jim but will try to help. When you are driving and the engine stops sudenly it can be Ignition or fuel so you need to do a couple of simple tests to get into the area of the fault. The Stromberg carburetor had no accelerator pump so pumping the pedal does nothing.
It is easy to divide up the problem between Ignition or fuel by just putting a timing light on the coil wire and tape the trigger down and run the light out from under the hood and put it under a wiper arm so you can see the light.
If you are doing this in bright sun light just tape a piece of cardboard over the light area on the windshield so you can monitor the light while driving. While driving at 50 MPH and it shuts down, quickly look at the light to see if the flashing has stopped. If not, it is for sure a fuel problem.
Fuel pump supply is the next test. For this you will need a fuel pressure gauge with a "T" connection (sometime it comes with a fuel pressure gauge) These gauges are not expensive. Put the "T" on the fuel line that goes into the carb. and a short from the "T" to the carb. Then put the gauge line on the last part of the "T" and run the gauge out from under the hood and put it under a wiper arm like you did the timing light test. (Use clamps on all of the hose fittings even if they fit tight. Now, road test again and when the engine quits read the fuel pressure gauge to see if you have lost pressure for a short time.
This tells you it is fuel supply or not. If not it is a carb problem, If it looses pressure then it can be several things, fuel pump, fuel line pinched or clogged, fuel filter clogged, fuel tank vent stopped up or fuel tank pick-up in the tank stopped up.
Don't blame the fuel pump right away, raise the car on a lift or on stands and remove the line to the pump from the tank and let it down into a gas can or such. (Keep a fire extinguisher handy any time you work around gas) Note if the fuel drains in a smooth continuous flow, this will check for most of the other problems. If the flow is not a good smooth continuous flow open the gas cap to see if it is venting problem.
Let me know,
Howard
