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Vapor lock question


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Bees and their kind are very industrious, hence "busy as a bee"

You should see wasps and hornets build paper nests!

Ever open up a dobber nest? Full of catatonic spiders, what a way to go. I also noticed I dont have a pick up screen on the sending unit. Im gonna fill it up and add a screen to it.

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Ever open up a dobber nest? Full of catatonic spiders, what a way to go. I also noticed I dont have a pick up screen on the sending unit. Im gonna fill it up and add a screen to it.

Yes! 🕷️

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Yes! 🕷️

Well, Added more gas cleaned the lines put a new screen on the pick up tube cleaned the fuel filter and AS SOON as i start to hit operating temp The filter begins to be less and less full until its struggling for fuel again. Got to be the Fuel pump?

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Well, Added more gas cleaned the lines put a new screen on the pick up tube cleaned the fuel filter and AS SOON as i start to hit operating temp The filter begins to be less and less full until its struggling for fuel again. Got to be the Fuel pump?

have you tested it? you are probably correct, yet you will be more confident if you test. it's strange that it works on a cold start though. I can only guess as to why.

this is NOT a diagnosis! just a theory. after sitting in this heat overnight, the carb may have dried out enough to lower the fuel level and lessen the resistance of the needle and seat. allowing less head pressure to the pump, allowing it to move fuel even at a lower pressure... as it gets full and shuts off the seal then the head pressure could be keeping the pump from drawing from the tank if there is a breach in the pump diaphragm. unfortunately, the pump is awkward to get to on this vehicle. try to do it from underneath even if you have to remove the oil filter to have somewhere to swing a wrench. if not then it is easiest if the power steering pump is out of the way first. this can include removal of ac, power steering pump assembly including brackets. they do not need to move far, just a few inches forward. and there is the power steering support bracket that arches over the fuel pump and shares the mounting bolts. I'm sure all of these are spotless clean, and color coded for easy access like mine. haha

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have you tested it? you are probably correct, yet you will be more confident if you test. it's strange that it works on a cold start though. I can only guess as to why.

this is NOT a diagnosis! just a theory. after sitting in this heat overnight, the carb may have dried out enough to lower the fuel level and lessen the resistance of the needle and seat. allowing less head pressure to the pump, allowing it to move fuel even at a lower pressure... as it gets full and shuts off the seal then the head pressure could be keeping the pump from drawing from the tank if there is a breach in the pump diaphragm. unfortunately, the pump is awkward to get to on this vehicle. try to do it from underneath even if you have to remove the oil filter to have somewhere to swing a wrench. if not then it is easiest if the power steering pump is out of the way first. this can include removal of ac, power steering pump assembly including brackets. they do not need to move far, just a few inches forward. and there is the power steering support bracket that arches over the fuel pump and shares the mounting bolts. I'm sure all of these are spotless clean, and color coded for easy access like mine. haha

I can't find the 351 in the 85 or 86 EVTM's Gary has posted.

If it were a 460 I'd say it is getting full voltage in prime (while cranking) and the pump is too sluggish to provide fuel in run (with the resistor)

But I only know HFH, and not whatever a 351 Bronco is wired like.

I still don't know if it is EEC IV (2V) or H.O. (4V)

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I can't find the 351 in the 85 or 86 EVTM's Gary has posted.

If it were a 460 I'd say it is getting full voltage in prime (while cranking) and the pump is too sluggish to provide fuel in run (with the resistor)

But I only know HFH, and not whatever a 351 Bronco is wired like.

I still don't know if it is EEC IV (2V) or H.O. (4V)

well, I was assuming 4v as that's all I have dealt with in f series. I hadn't considered the early tbi like some cars got.

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well, I was assuming 4v as that's all I have dealt with in f series. I hadn't considered the early tbi like some cars got.

Not injection.

150 trucks (and Bronco's) got the feedback carb, or could be optioned with the H.O.

I'm trying to make sense of this, but I don't know what we're dealing with.

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Not injection.

150 trucks (and Bronco's) got the feedback carb, or could be optioned with the H.O.

I'm trying to make sense of this, but I don't know what we're dealing with.

Its a mechanical pump, and I cant literally watch the fuel drop out of the filter at exactly the same point in time. How would I test the pump? I do notice that when it starts to drop its almost like air is in the line, as it bubbles up into the clear filter with each stroke of the motor. Im going to check the tightness of the pump.

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Its a mechanical pump, and I cant literally watch the fuel drop out of the filter at exactly the same point in time. How would I test the pump? I do notice that when it starts to drop its almost like air is in the line, as it bubbles up into the clear filter with each stroke of the motor. Im going to check the tightness of the pump.

Ok, so it's definitely an HO that came with the 4180.

How is your oil level?

Does it smell like fuel?

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Ok, so it's definitely an HO that came with the 4180.

How is your oil level?

Does it smell like fuel?

Oil level is a low and I FEEL like it smell like gas, but now that I've smelled it about 10 times idk, I may be high now.

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