Fuel line

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eskimomann209

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Forgot to mention that the return line keeps the fuel circulating which keeps the fuel cooler.
This works better when the filter is further from the carb as well... ‍♀️
Like down low on the frame rail. I think your stealing ideas from an FI system and hoping they work on the carb setup.
It’s the traveling in the return that gives off the heat. I think your return line is so short it’s kinda a moot point
 

Backfoot100

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This works better when the filter is further from the carb as well... ‍♀️
Like down low on the frame rail. I think your stealing ideas from an FI system and hoping they work on the carb setup.
It’s the traveling in the return that gives off the heat. I think your return line is so short it’s kinda a moot point

Respectfully have to disagree....sort of.
Yes, it keeps fuel circulating.
No, as in putting it close to the carb is not defeating the purpose.

Several people here still experience vapor lock with a three port mechanical pump that has a return to the tank from the pump. That still causes problems because the fuel line from the pump to the carb is dead-ended at the carb and heats up with nowhere to go except to the float bowl. While sitting stationary (in traffic with the engine running) and the carb using very little gas it just heat soaks the line and fuel in it.
Having the return closer to the carb eliminates that heat soak by keeping the fuel moving and carrying away any heat it does pick up.

The biggest key is having a return line which the factory started incorporating with the three port pumps but its been proven that sometimes isn't enough.
 

eskimomann209

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Respectfully have to disagree....sort of.
Yes, it keeps fuel circulating.
No, as in putting it close to the carb is not defeating the purpose.

Several people here still experience vapor lock with a three port mechanical pump that has a return to the tank from the pump. That still causes problems because the fuel line from the pump to the carb is dead-ended at the carb and heats up with nowhere to go except to the float bowl. While sitting stationary (in traffic with the engine running) and the carb using very little gas it just heat soaks the line and fuel in it.
Having the return closer to the carb eliminates that heat soak by keeping the fuel moving and carrying away any heat it does pick up.

The biggest key is having a return line which the factory started incorporating with the three port pumps but its been proven that sometimes isn't enough.

The way I’m seeing this is it travels into the bowl from that filter then Right back into that little filter on the return side. To mix with now freshly pumped gas. That short time from the over heated bowl right back into the filter is enough time to dissipate the heat?

Well then carry on gents
 

Backfoot100

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The way I’m seeing this is it travels into the bowl from that filter then Right back into that little filter on the return side. To mix with now freshly pumped gas. That short time from the over heated bowl right back into the filter is enough time to dissipate the heat?

Well then carry on gents

I believe its the other way. Fuel comes into the filter and is routed back out again on the return. There's a seperate port that comes out of that and to the carb so only a few inches of fuel line is all that's dead-ended at the carb.
 

eskimomann209

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I believe its the other way. Fuel comes into the filter and is routed back out again on the return. There's a seperate port that comes out of that and to the carb so only a few inches of fuel line is all that's dead-ended at the carb.
So he bypassed the return line that actually runs through ( out) the carb?
 

Backfoot100

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So he bypassed the return line that actually runs through ( out) the carb?

No.

There's a small restriction in the return line on the filter that allows fuel to be returned to the tank. It doesn't go into the carb and back out again.
 

fussfeld

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So he bypassed the return line that actually runs through ( out) the carb?

I'm not aware of a return outlet that runs out of the carb/(a quadrajet)?

Really, the way i have it arranged is all due to what pieces i had on hand at the time---i needed the truck running ASAP, and i wanted the filter to lay flat horizontally. And that's the best i could come up with for now. May not be the best layout, but it will and does work for now.

Now that i think about it, having the return that close to the carb may be better in that there's not a whole lot of fuel that cam boil----only a few inches between return outlet and carb inlet----as Backfoot pointed out.

Will talk later on the weekends----too busy now.
 

fussfeld

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This works better when the filter is further from the carb as well... ‍♀️
Like down low on the frame rail. I think your stealing ideas from an FI system and hoping they work on the carb setup.
It’s the traveling in the return that gives off the heat. I think your return line is so short it’s kinda a moot point

Maybe i can get a better pic this weekend, but my return line goes all the way back to the tank; Maybe you can see in the pics that it goes behind the alternator and if you look to the left of the alternator near the framerail you might see it reappear again.
 

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