Fuel line on my 76 Blazer

[ike]

1/4 fuel return line

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Quote:
Originally Posted by btolenti
the 5/16" is the EVAP line
the 1/4" is th fuel return from the pump
the 3/8" is the fuel supply line to the pump
THe large one is the vent for the fill tube.



Can I cap the hookup for the return line at the pickup and run a fuel pump with one inlet? Why do I need or want this return line??

 

[pauly383]

Why not run the fuel pump with the return line , since its already set up like that ?

Are you planning on running the pretty aftermarket fuel pump ?

 

[ike]

chrome will get me home

No not all ..LOL I was thinking about a new , aftermarket , (Made in Mexico) , nstead of a parts shop , (Mexico) , rebuild.Thought it might be simpler to remove non needed items....

More then anything I wanted to know what the return line was for....Why have it? I own and have worked on several pre 70's American cars and don't think I have ever seen a return fuel line from the fuelpump
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From reading the posts it seems the return line is to keep cool fresh fuel to the carb. Sounds good...I'll find a new (Made in Mexico )fuel pump that will work as a stock replacment.

Now I have a question regarding the tank vent...My tank was set up with the vent right on top of the tank...There was a 3in hose with a little plastic fitting like the one used to vent the diff. The set up looks original OEM.Seems it would be better to at least extend the hose up ...maybe fasten it to the fill neck....to keep fumes from gathering under the truck and keep it from the road dirt ,water ect.......
I would (and have) paid extra for non-chrome (Made in Mexico ) parts.

 

[pauly383]

Dorian answered that in your other post . The one with the return should feed your engine fine , and prevent vapor lock .

And there is supposed to be a vent right to the fill neck , at least on the trucks I have seen .

 

[dyeager535]

You are talking about the actual small vent line off the sender, not the large fill neck vent, correct?

The only things to be concerned with when venting a tank is that you don't want the fumes near ANY ignition source of course. You don't want it exposed to humidity if possible, but that's pretty hard to do without EVAP or a low PSI vented gas cap. Lastly, I've heard that the gas vapor hurts paint in the long run (and that makes sense) so venting it against anything painted is probably not the best approach.

 

[ike]

the large vent to the neck

On my truck....The large line goes to the neck to vent when fueling...the fuel cap is non vented so that will not vent the tank at any other time...The small line fron the sending unit is the vent and it just has a short line with a diff type plactic fitting "vent fitting" on it ....The question is ....Is this OEM It looks like it....and can I or should I improve it in any way....IE....Run a longer line or a differant type vent.....???

 

[dyeager535]

It's impossible for me to say thats how those things were or were not vented back then. (this is a '76 or 74, right?)

All the newer stuff vents through the EVAP cannister, but I've got a friend with a 1983 C30 that does not have EVAP, and appears never to have had it. Unless I pull the tanks, no way I'll ever know how they are vented. I suspect like yours is, but as old as these trucks are now, unless you were the original owner, there is no way to say what's factory and what wasn't unless its documented. MAYBE a '76 manual will show that, but I doubt it.

 

[ike]

76 fuel tank vent

I think its factory...I think I'll put it back the same way but extend the vent hose up and away from the road and out from under the truck a bit...