First Truck, Help please!
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From: Virginia
This article explains it some. Scroll down just before they start talking about electric pumps. The return spring sets the pressure.
https://www.howacarworks.com/basics/...uel-pump-works
https://www.howacarworks.com/basics/...uel-pump-works
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The truck is on a pretty flat area, or at least i would hope so considering it is in a garage. And no, its not lowered or lifted. I like the stock ride height just fine. I got my fuel pumps, as well as everything else for the truck, through carquest if that makes any difference to anybody.
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Anyways, I think you're on the right track with your observation about how the truck ran okay (for a short while) after you disconnected the fuel supply from the carb. I'd suggest seeing if you can repeat this, and go from there. Keep up the good work, a tip of my orthopedic hat to ya for the good troubleshooting.
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Basically every time I can do the same thing. Hook up fuel line, let the pump fill the carb. Disconnect the fuel line, and the engine will start and run almost perfectly. Mixture might need adjusted a hair but not much. I really cant think of anything It might be other than a wonky float/adjustment or too much pressure from the pump. I am really hoping its the pump. Something interesting I found, I think the fuel pump I got is for the trucks made in Canada. Not for sure, just looking at the one I have compared to carquests website. Would that make any difference?
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I doubt it. It does sound like it's overflowing, I just thought you might want to verify that. You never know, the float may have a pin hole in it. Then it fills with gas and sinks, and never cuts the fuel off. I don't know if you have ever been inside a carb, but they work much like a toilet works with a float to cut the water off. The carb float cuts the fuel off.
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I doubt it. It does sound like it's overflowing, I just thought you might want to verify that. You never know, the float may have a pin hole in it. Then it fills with gas and sinks, and never cuts the fuel off. I don't know if you have ever been inside a carb, but they work much like a toilet works with a float to cut the water off. The carb float cuts the fuel off.
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From: Virginia
If it was a brass float you can shake it and if it sloshes it has gas in it. Since you have the foam type float, you can squeeze it a little bit and see if gas oozes out of it. They are less likely to fail. I know you just bought a brand new carb, but you could take it apart and take a look inside and see what you can see in there. May be something got dislodged in shipping.
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If it was a brass float you can shake it and if it sloshes it has gas in it. Since you have the foam type float, you can squeeze it a little bit and see if gas oozes out of it. They are less likely to fail. I know you just bought a brand new carb, but you could take it apart and take a look inside and see what you can see in there. May be something got dislodged in shipping.
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From: Angier, NC
If you can find a new float how long do you think it would take to get it in your hand? You have the other float right so that would be just time to pull the carbs apart to do the float swap.
Dave ----
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Alright. That makes sense. I guess ill start with getting a fuel pressure gauge and if thats ok, then I'll pull the carbs apart. How far out of spec can the fuel pump be to be useable? The stock rating was 6-8psi, so does it HAVE to be within that range or can it be 5 or 9, for example?
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From: St Albert, Alberta
Alright. That makes sense. I guess ill start with getting a fuel pressure gauge and if thats ok, then I'll pull the carbs apart. How far out of spec can the fuel pump be to be useable? The stock rating was 6-8psi, so does it HAVE to be within that range or can it be 5 or 9, for example?
On the low end it can be as low as 2 PSI provided it can supply enough volume it will affect float hight if to low... On the high side depends on that carbs particular needle and seat before it starts to push past it. again it will affect float hight. You may be able to take 15psi with no issues or it could start pushing past the carbs needle and seat as low as 9 psi. A new needle and seat will have a higher threshold than an old one typically.
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And here it is Monday already. Any updates? We're all anxiously awaiting the part where you have solved the problem and announce that I was correct. Again. As usual. 
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Sorry I havent posted for a few days, Ive had another project ive needed to get going. Now that thats done, Ill go out and figure the problem out as soon as I can stand to go outside in that heat again lol