fuel return line questions

[gmc4cw]

this may be a dumb question. I have a fuel cell. can I run the fuel return line into the bottom of the cell? how much pressure is there on the return line versus how much pressure would the there be from fuel pushing down in from the cell? there are 2 fittings. one I am using for the fuel feed. I have a fitting on top of the tank I can run it too but if it will work the lower fitting would be better for my setup.

this is how I have the cell mounted. I run the feed off one of the lowers. I could run the return into the upper left.

I realized after the last trip out that I needed a return line. The truck stalled a lot and didn't fire right up when I tried to restart it every time. It didn't do that before I plugged off the return line. I guess its flooding the carb and thats causing the stalling and hard starts since thats the only thing that changed. I needed to get it put back together quickly to make the ride.

I am running a stock mechanical fuel pump off the side of the motor.


No one needs to mention the breather line. it's already taken care of.

 

[Jason4x4]

i wouldn't run the return line into the bottom, because the fuel will be pushing out of the tank, and the pump probably wouldn't be able to force fuel in the bottom.

 

[gmc4cw]

thats kind of what I figured but it doesn't hurt to ask the dumb questions. anybody wanna donate a couple of feet of braided stainless fuel line?

another dumb question. other then cost, is there a reason I should NOT run all my lines with braided stainless. the stock line has sections of rubber hose in it now. since its no longer a stock application do I need to use hard steel lines?

 

[dyeager535]

I like solid lines where possible. Less problems. Don't care what anyone says, braided lines aren't solid. In your location, at least stainless though I'd think, even solid.

Use braided to replace the rubber sections that need to flex.

 

[gmc4cw]

I like solid lines where possible. Less problems. Don't care what anyone says, braided lines aren't solid. In your location, at least stainless though I'd think, even solid.

Use braided to replace the rubber sections that need to flex.

in your opinion what about solid makes it have less problems?

I was looking at like this. I can run one single piece from the tank to the pump and its very easy to route. If I replace the steel line with new steel line I still need small sections of rubber hose to hook it all up. every connection is a potential leak. Keep in mind that this on a truck that is only driven offroad and only a few times a year. I use stainless for everything that has to be a hard line. I buy pre bent from www.Rightstuffdetailing.com I have their brake lines and trans cooler lines. since the fuel system is low pressure is a hard steel line necessary?

 

[dyeager535]

Braided lines can fail, you'll never see it coming. With steel at least you have a better chance of seeing a failure coming. Braided lines are still some sort of rubber/teflon/whatever type of material underneath the pretty covering. (I am talking about the good OEM stuff, not the Spectre dress up stuff of course)

Braided lines still can't take heat, if for whatever reason your lines get close to a heat source, a metal line isn't going to rupture.

Metal lines are more rigid. For throwing debris, sticks, rocks, etc., the better the lines stick to the frame, the better. To get even close to the same rigidity with braided, you'd need a hell of a lot of clamps to the frame. Note that the stock fuel pump to carb line never touches the block, yet requires no additional components to achieve that.

Since the metal lines are rigid, if mounted correctly, abrasion is a non-issue. Any flexible line usage has to take this into consideration, a sharp edge will cut through the braided stuff pretty effectively if left alone. Since it's not rigid, it WILL move wherever it's not clamped, however slight.

The fewer connections the better. I've not looked at braided line in a long time, but I would imagine getting a full length run of braided stainless line of good quality to be expensive.

Solid is certainly more of a hassle to deal with, (routing, bending, etc) but short of potential ease of install, I don't think there is one advantage to braided line in an application that solid can be used. Ease of install is pretty meaningless if you are talking one install for the life of the vehicle.

Potential failure at the rubber connections is a possibility, but with no sun exposure, no pressure, and protected areas (only run from frame to pump and from tank to frame) the likelihood of those causing problems is quite slight. If I was that concerned about it and wanted to do it once, I'd run solid lines setup with the Saginaw ends (the EFI style with o-ring) so that I could use factory braided stainless stuff at the joints. Even less leak prone, and very secure.

Yes, I overthink stuff. Will my truck ever burn? Nope.

 

[gmc4cw]

Thanks, good points. sometimes my laziness over thinks itself. braided would be easy to lay in place and I'm getting tired of being under my truck. but your right that I would have to put more work into securing it.

I guess another call to Right Stuff is in order.

 

[slyguy_22]

even on my tbi setup it has some sections of rubber hose. im sure you wouldnt have any problems. hard lines smash against rocks and stumps and such. rubber lines you can atleast patch pretty quick on the trail. only problem with rubber it detoriates in extreme heat and cold. (like sitting alot in the snow over winter). sent ya a pm bout the boxes