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Discussion Starter #1
i have a problem with the fuelline in my 69 Camaro 350 cui. I believe, that the pre-Owner installed the line incorrect. The line comes from the fuel pump upwards, behind the alternator and then with a sharp buckling across the engine to the carburetor. Is this the correct course? Because i have the problem of gas getting to hot.

Here is a link to my german V8 Club. It is a picture of my fuel line. You can see the buckle behind the alternator bracket and the fuel line fixed with cable clips at the cooling water hose.

http://www.ami-stammtisch.de/mediagallery/media.php?f=0&sort=0&s=20100923071652458

Maybe someone has a picture of the original installation.

Thanks a lot and sorry for my english.....;-)
Mike
 

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Re: fuel line, how to install it?

Best I can tell from your photo - someone has run a 'fools-plumbing-nightmare' of rubber tubing from the original steel fuel line (from fuel pump) to the carb (a Holley by looks) inlet(s) :sad:

The only recommendation I would have is to refit the vehicle with a 69 and later 'Z28' type fuel line set-up for a Holley.
Here is a link to the parts needed - http://www.google.com/imgres?imgurl=http://shop.stevescamaroparts.com/images/1213210356698725341973.jpeg&imgrefurl=http://shop.stevescamaroparts.com/69-72-Holley-fuel-line-w-brass-Y-block-Camaro-z28-302-290-hp-130420.htm&usg=__V4j2tY2y-Pk24Ez6XE11fqLRbb8=&h=76&w=175&sz=8&hl=en&start=1&zoom=0&um=1&itbs=1&tbnid=T95iAl8F8DmD4M:&tbnh=43&tbnw=100&prev=/images?q=Z28+302+oem+holley+fuel+line+photos&um=1&hl=en&tbm=isch&ei=O4qLTZ7GIYT0tgPxgv2gCg

This may take some minor re-bending or rework to fit nicely, but it should correct the issue. :thumbsup:

Hope other chime-in with input
 

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Re: fuel line, how to install it?

Vintage,
Does that fuel line (in your link) "bolt on" to a standard 350 w/ mechanical pump and a Holley? Does it go behind the alternator? Is there a length of rubber hose somewhere in the equation?
Thanks,
John
 

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Re: fuel line, how to install it?

Vintage,
Does that fuel line (in your link) "bolt on" to a standard 350 w/ mechanical pump and a Holley? ...
Yes, it is made for the standard SBC Fuel Pump to dual inlet Holley carb. set-up as used on some 327's and the 302.
The installation would be the same dimensions (+/- a small tweek here or there dependant on manifold flange height) for any given SBC.

Vintage,
Does it go behind the alternator? ...
Yes, it routes from the fuel pump up behind the alternator and bends at the manifold back to the passenger side of the carb.

... Is there a length of rubber hose somewhere in the equation?
Thanks,
John
No :eek: there should be no rubber hose from the fuel pump to the carb. (pressure side).
You're asking for issues when rubber hose is run in these areas :yes:
 

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When you get the duel inlet fuel line for your Holley carb. , make sure you order the correct size. They are made with 5/16" inlet size and 3/8" inlet size.Also with the correct spacing between fuel bowls. I agree with the others--NO rubber lines sould be used.
 

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Discussion Starter #7
Thanks for the pictures, but my Holly looks different. It only has one fuelinlet and thats on the other side.

We now tried to fix it with using aluminized fuellines. But yesterday, i broke down again because the gasoline got too hot....

I think, the main problem is, that the engine bay cannot breathe enough. There is no way, where the hot air can disappear. So the problem only appears while waiting in a traffic jam.

We now want to try the Holly Heat Shield. Hope, that we can get the problems under control by this way. If not, i think about drilling some holes in the front panel to get more fresh air to the engine. Also i started thinking about installing the Original "SS" Hood Ornaments. Using them to evacuate the hot air from the bay. I know, that they are normally not open to the engine bay.

Does anyone else have more ideas?
 

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Not sure what you have going on there but Holleys don't utilize return lines. And throw that glass fuel filter in the garbage. They have been known to fail. Many years ago it was the cause of a friend's engine fire and the car burned to the ground. Hardlines are best as suggested above. The holes in the radiator support you are contemplating will decrease the amount of air passing through the shroud, thus reducing cooling system efficiency.:)
 

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Discussion Starter #10 (Edited)
well, i´ve bought the car like it is on the photo.... It is a 1805 Holly 4bbl universal carburator. You mean, i dont need a return line? What about using the heat shield? And what filter would you recommend? Can i use an universal filter?

I have thought about changing the Holly in to a Edelbrock ede 1406 600cfm. I´ve heard, that they have less problems with steam bubbles

The holes in the radiator support you are contemplating will decrease the amount of air passing through the shroud, thus reducing cooling system efficiency.
But how can i get a better cooling of the engine bay?

Not sure what you have going on there but Holleys don't utilize return lines.
i have the original Chevy SB mech. fuelpump. If i dont use a return line, how does the pump knows, that there is enough gas at the carburator? Won´t the pump work all the time? And if yes, where will the no more required gas go? Or does the pump has an internal bypass? please explain...
 

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Here are a couple more shots showing a filter, fuel pump and hard lines to the carb. Sorry they are not the best but you can see the filter is before the the inlet to the fuel pump and not on the pressure side out to the carb.

I don't think the problem you are having is heat related as much as it is your make shift return (backflow) hose that is bleading off needed fuel pressure. Fuel will take the path of least resistance. I assume the return line goes back to the inlet side of the pump and if so that is defeating the efforts of the fuel pump. Plug off the return line and see what happens...

Your engine compartment (like everyone elses) should not need custom venting to allow the engine to operate properly. If your engine is overheating when you are sitting at a long light you need to look at air flow through the radiator core and your cooling fan which creates that air flow. If the engine isn't overheating I doubt the engine compartment is getting too hot...
 

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Some cars were equipped with dual fuel lines, for example a SS350 with a Quadra-Jet Carb. I believe the fuel filter used with the dual fuel lines is designed to return heat created fuel vapor back to the tank, it's not recirculating the liquid fuel or bleading off fuel pressure.

If your car has 2 fuel lines from the tank you need the right filter with a single inlet and dual outlets to connect the return properly...
 

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Discussion Starter #14
@dennis: i assume that there is no backflow line on your photos?

@sauron: only to get it right: no filter on the pressure side (like i have) but one in front of the pump?

Only one thing i don´t understand: what happens with the fuel which is not needed? I mean, the pump is pumping all the time, so what happens, if the pressure in the hose is getting to hot?

What are you saying for the aluminized fuel lines? Are they ok? Because i can´t find any fitting hardlines for that particular carb.
 

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Well I have never seen a single issue caused by putting the filter on the inlet side of the fuel pump. I have 10's of thousands of miles on my own car and previous cars done the same and have set up many friends cars the same. Unless the filter gets plugged I can see no reason why it would flow any less or reduce the flow from the tank to the pump.

If there is a need to filter the fuel, wouldn't it be a good idea to do it before the fuel pump and protect the pump from what the filter picks up?

As for the use of the return line on q-jet carbs it may well be part of a smog thing and there because of the nature of the carb itself or for rollover fire protection. I don't have the details but I do know the return line from the filter is primarilary a vapor return. As this relates to Mike's problem he has a return tapped into his fuel feed to the carb that transports liquid fuel either back to the tank or the fuel pump inlet and that almost makes his fuel pump useless...
 

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@dennis: i assume that there is no backflow line on your photos?
No return line.

@sauron: only to get it right: no filter on the pressure side (like i have) but one in front of the pump?
The info he provided says to put the filter on the pressure side not in front of the pump. I don't agree and posted a reply to that...

Only one thing i don´t understand: what happens with the fuel which is not needed? I mean, the pump is pumping all the time, so what happens, if the pressure in the hose is getting to hot?
The mechanical fuel pump should not typically create too much pressure. Some aftermarket performance mechanical pumps might require a pressure regulator like an electric pump does... The pump is pumping all the time the engine is running but at the same time the carb is using the fuel. Why are you fixated on the fuel lines getting too hot? Is your engine overheating?

What are you saying for the aluminized fuel lines? Are they ok? Because i can´t find any fitting hardlines for that particular carb.
If that's all you have but I would think you could find some steel brake line to use...
 

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Discussion Starter #17
Why are you fixated on the fuel lines getting too hot? Is your engine overheating?.
No, my engines temp might be ok. The water temp always ranges between 180 - 188 degrees fahrenheit. But for some reason, the fuel is getting to hot.

I will try the tip with the return line and the fuel filter. Maybe thats the problem.
 

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Well I have never seen a single issue caused by putting the filter on the inlet side of the fuel pump.

As this relates to Mike's problem he has a return tapped into his fuel feed to the carb that transports liquid fuel either back to the tank or the fuel pump inlet and that almost makes his fuel pump useless...
I saw his incorrectly plumbed lines. I was curious about your filter's location. I'm aware you run your car like this and was looking for more data. That's why I asked. If I were to relocate one it would then be of no concern to me.
 

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Don't get so hung up on the fuel pump pressure. A mechanical fuel pump mainly pulls fuel from the tank. The pressure it's able to supply on the outlet is related to the diaphragm design. Once the pressure is reached, the diaphragm basically just flaps away without moving more fuel until the engine can suck more in.

Take in a breath of air through your nose and blow it out through your mouth. Do this in a cycle several times. Then seal your lips and press your finger over them while continuing to try to suck in through your nose and blow out through your mouth to continue breathing at the same rate. You will find that to keep operating, you have to blow your breath back out of your nose. That is similar to what is happening with the mechanical pump.

On that simple little single inlet Holley you should have the pump line going to the carb inlet and that's it. The only time it is necessary to regulate the pressure is when a high pressure pump is used which is able to supply more pressure than what the carb is rated for (around 7psi for the common Holley).

There are plastic versions of the glass filter that you have which work well. The carb itself also has a brass filter inside the inlet to help catch trash.

Your "bypass" line is likely your main problem as you are not able to maintain pressure to the carb. Remove that and then if necessary you can adjust your float levels and further tune the carb.

http://www.holley.com/0-1850S.asp



 

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Greetings from Arizona
Where does that RETURN line go? all the way to tank? if you look at my photobuckets there are several pictures of fuel lines I've made for our projects. I always use brake line and bend it to fit. clean it and paint it. infact I bend all fuel, transmission, vacumn lines for custom fit and we try to hid them best possible. Very true about those glass filters... friend almost burned his car and garage down last year when one blew up!
I try to put my filters before pump or back at tank. Good Luck! Jay
 
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