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I have a '52 convertable that looks to have been decently restored a few years ago.

Occasionally it will die at a stop and then refuse to restart. Generally it starts right up hot or cold. The first couple times this happened i hiked to a gas station and put a little gas in and it started right up, so I assumed the gauge was off and I ran it out of gas, but it would not take a full tank on refill.

I had a leak at the sending unit so I pulled the tank - it is spotless inside, I assume it was refurbed during the restoration. Lines are similarly new and clean, I shot air through them to be sure. I cleaned the carb - there was some mild gunk. I also installed an electric fuel pump inline as a back up at the tank. I tested the mechanical one to about 6-8 lbs pressure so I think the fuel pump is OK.

I have driven it a bit (but probably no more than 100 miles off and on) with no issue. But it happened again yesterday with definately a full tank. I have a dry cell battery, so I can crank this thing till the cows come home, but could not restart even with the electric fuel pump on. I dumped some gas down the card and it did start with difficulty. It caught and took a few seconds of nursing it to build up to speed - somewhat like it was flooded. Then it idled and ran fine - all 1/2 mile to my garage.

This feels like a fuel problem to me, but I can not seem to track it down. I can try fully rebuilding the carb. I also have NOT touched the mechanical fuel pump - which is infront of the electric pump. I think the electric pump should push through the mechanical one if it is an issue, but maybe something is getting plugged in the mechanical pump restricting the fuel flow. In the past. once it has restarted, it has not come back on the same trip.

I have an inline filter at the carb that I changed out when this started.

This is unpredictable, except it is always likely to be a busy intersection, so trial and error is frustrating. Most the times this has happened, the engine has been at operating temp, but definately not hot. Yesterday it was right out of the garage, not yet to temp. I do not think this can be a vapor lock of some sort.

I am not very familiar with the '52. Is the next step the fuel pump?

One of several possibilities is that with your electric pump pushing thru the unrebuilt mechanical pump, if the diaphragm in the mechanical pump has failed, the electric pump is pushing some (most?) of the gas directly into the crankcase rather than the carburetor. Pull the mechanical pump and rebuild it or have it rebuilt by someone like Gould or Terrill as a first step. And if this has happened your oil has been very diluted and should be dumped or you will risk real serious engine problems.

One last comment, the needle and seat control valve is the carburetor is designed to function with a maximum pressure of 4.5 to 5 psi so your electric pump could overwhelm it - after you resolve the other issues, install a pressure reducer and only use the electric pump for priming after long storage, or if vapor lock should occur.

If you get the pump rebuilt the rebuilder will take care of the cleaning but if not, on some pumps the steel bowl on the bottom has a stacked plate arrangement inside that acts like a screen. Other pumps have ordinary screens inside the bowl. If the tank was rusty at some point all those rust particles could be inside blocking flow.

Another thing would be the rubber flex hose between the pump and main fuel line. If that wasn't replaced it could be old and the liner inside could be cracked. With cracked liners the pump could be managing to pull a portion of the liner away from the wall and block fuel flow. If hose is not alcohol resistant it might have swelled and not allow much flow.

Thanks for the quick reply - I should have mentioned that the electric is only a stand-by. It was off when this occurred, but turning it on failed to help start the car.

I will order a rebuild kit and see what the pump looks like inside. It does not appear to have been rebuilt, but so far everything I have gotten into in this car has been surprisingly new/clean.

There is no indication of gas in the crankcase, but I'll check next time I am in my garage.

Good call on the pressure reducer. I will check the specs on the pump, I don't recall the output pressure.

The small rubber hose has been replaced. It looks like the consensus is going to the pump. I'll let you all know if that fixes it.

Thanks for the helpful insight.

coil? capacitor? vacuum advance? dirt in electric pump filter?

Good advice from all. There is one more thing you can easily do. Check the gas cap. It should be a vented type. An unvented cap can cause engine stalling.

(o{}o)

remove ditributor cap and rotor. Shake the distributor shaft back and forth sideway to see how much slop/wear there is in the bushings.