Vacuum secondary.
Thats a great idea.
Checked the filter. Clean as a whistle. I hate shmutz, which is a yiddish word for poop by the way.
Vacuum line to wipers is pugged for testing.
I have checked the fuel line from the tank to the fuel pump, but Im gonna put it on the lift right now and check it again. I wonder if I have a pin hold that is not leaking gas, but is sucking air. I may do the nurse tank test tomorrow, and drive that hill. That will eliminate everything south of the fuel pump. Bad pump lobe in the engine?
Schmutz means dirt. The word for the other thing is “dreck”
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Your yiddish is impressive!
Thank you.
Perform a fuel volume test. Disconnect the fuel line from the carburetor, connect a piece of hose to the fuel line and put the end of the hose in a container. Start the engine, it should pump at least a pint in 30 seconds.
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good idea.
I agree with the comment that if the secondaries weren’t opening, your engine wouldn’t die, it’d just be weak. If they are opening but no gas is added, then it’ll die.
Your secondaries don’t start to open until you are 75% throttle. They are mechanical but have a vacuum line attached to the linkage to prevent them from opening when the vacuum is below 3". The secondaries require both >75% throttle and >3" vacuum to open.
I believe that you are correct that the engine is starving for gas. I still think the problem is something trapped in or below one or both of the main jets. I think you will need to access the main jets, unscrew them and then use a spray can of Gumout to spray opposite to the flow of fuel to get it out.
But, it could be in the fuel line or filter or fuel pump. If you come to a hill or otherwise stress the engine, if it cutouts immediately, it’s in the carb. If it runs strong for a few seconds, then it could be upstream of the engine. BTW, are you sure there is no restriction in the exhaust? That could also cause this kind of problem.
Edit: easy to check exhaust, just put your hand over the exhaust pipe and have someone work the throttle a little. You should feel good flow and instant changes with the throttle changes.
Maybe the exhaust is restricted from critters living in there?
Tester
If you have a vacuum gauge, it can tell you a lot
https://www.gregsengine.com/using-a-vacuum-gauge.html
Just did the nurse tank test using a hand pressure bulb instead of fuel pump. Connected it directly too carb. Car did not die on the hill. The only thing we have not replaced is the main fuel line from the tank to the fuel pump. But that has good flow and we cant find any leaky pin holes in that line. I think next we will connect a temporary rubber fuel line from the tank to the fuel pump to see if that line is constricted or has pin holes. Seems to me if it was sucking air at high demand we would see gas seeping from that location.
And you would likely smell gasoline when the gas line pressure leaks down through the hole.
Ok, so we did a 30 second volume test on this fuel pump with a nurse tank, and it failed. This is the second new fuel pump. So here is my new theory. Maybe the motor in this car is not a 1957 312. Maybe, a previous owner replaced the original block with some other Y-Block that requires a different fuel pump. How crazy is this theory? We are looking for identification numbers now on the block.
Just to add to the confusion, low volume could also be from the tank to the pump? Or old pump stock with deteriorated diaphragms? I dunno. I do remember our 57 Fairlane with the T-Bird engine had a choke problem among other issues. Dad only kept it a year though so maybe there were other inherent issues that would have shown up. Good luck though. Looks like you are in good hands.
EZC-C. which means 1957 312ci. My theory is shot. I am out of ideas at this point. 2 bad fuel pumps in a row? Is that really possible?
If they were new old stock, yes. I went through 3 for my 62 Caddy. Call the place that rebuilt your carb, an ask if they could put a new Nitrile diaphragm in your pump.