fuel return line.

[chincha805]

has anyone put in a fuel return line with a stock 49 in cab fuel tank? i am using the stock tank with a carbureted 4.3 v6, and the fuel pump has a return line on it. i want to use the fuel pump the way it is because of the inlet and outlet locations coming from the front side of the engine, and not interfering with the headers and frame. it is a 1985 4.3 v6 factory carb'd engine

[01spirit750]

Yes I did this for my 57' with EFI.



There are more pictures in my gallery

It can only be done with a new sending unit.

I purchased a new fuel pickup/sending unit for my stock 57 tank.

I drilled a hole another in the sending unit and soldered in a line.

http://www.ebay.com/itm/1955-1959-Ch...item2828ab950a

http://www.ebay.com/itm/HARRIS-STAY-...item5438545eeb

http://www.ebay.com/itm/NOS-Jeep-CJ-...ZW4w27&vxp=mtr

[01spirit750]

I should mention that you need to remove the electrical connector on the fuel pick up flange during the soldering process (or you will melt the connector / isolator).

Here is a video I watched, skip to the 11 minute mark. I looped the solder around the tube 2x and then soldered it like in the video.

https://www.youtube.com/watch?v=OpMFQFi6Hh4

[jweb]

I had a threaded bung welded in the top of my tank toward the driver's side. If you choose this way, you will have to remove the tank and clean it really well first.

The sending unit idea might be easier.

[jweb]

Originally Posted by jweb

I had a threaded bung welded in the top of my tank toward the driver's side. If you choose this way, you will have to remove the tank and clean it really well first.

The sending unit idea might be easier.

I should have been more clear. I would never have attempted this myself. I had it done at a local Speed Shop, luckily we still have one here. I washed the tank out a dozen times with soap and water, and I believe he filled it with water when working on it.

It can be very dangerous when done wrong.

My first thought was to do it through the sending unit like posted above. But I had heard of possible fuel swirling issues. That's the only reason I went this route.

[mr48chev]

I'd suggest only doing that on a new tank that had never had gas in it though. Had a pretty good radiator guy get killed here in the valley a number of years back when he went to weld on a gas tank for a customer.

There are brass bulkhead fittings that could be installed in the tank to run the line to. I have had one in a stainless tank that sits in the front of the bed of my 71 for a long time. I use that one to install a new fuel pickup from the top of the tank rather than out the bottom of the tank where it was first installed as that one leaked and is sealed with JB weld now. You have to have it close enough to the sending unit hole so you can get your fingers in to put the nut and sealer washer on the inside and get a wrench on them. Something like this that you should be able to source locally and then use a copper of fiber gasket washer to seal it. http://www.ebay.com/itm/Threaded-Bra...3D291258986653

[01spirit750]

I strongly second the suggestion of only welding on a new tank, and even then fill it with water all the way to the top. The water helps displace any vapors.

REMEMBER: The vapor is what explodes, not the liquid. So an empty tank is the most dangerous item to work on.

[dsraven]

take the tank to a rad shop.they will boil it out (probably needs it anyway) and solder in whatever fitting you supply wherever you want it. take the sending unit out first. no kaboom that way.
another way would be to clean the tank. fill it with water to the top, so no vapour, then solder or weld on the fitting of choice. after that is done and you are satisfied there will not be a leak, you can drill the tank through the fitting. then drain the tank, add some methyl hydrate to help absorb the water, drain again and let sit somewhere warm to dry out completely.
for a return line it may be nice to have a short tube inside to direct the return fuel away from the sending unit float, they aren't attached all that well. sort of like a dip tube in a hot water tank.

[1project2many]

Heating / welding a fuel tank is safer with inert gas such as Argon or CO2 in the tank than water.

[chincha805]

i will have a rad shop boil it, then weld a bung on the top, the tank has been dry for 15 years, there ar no gas fumes at, if you looked in through hole with a flash light, it looks like it is new.

[55cruiser]

Empty gas from tank, and with a warmed up running vehicle, run a exhaust hose from tail pipe into filler neck. Let car run for a hour or so, weld up. Tank is filled with carbon dioxide will not explode as a explosion requires air (oxygen) Done it lots of times I am a poor old hot rodder. It works

[dsraven]

how about drilling the fuel inlet pipe from the tank filler? I am not sure if that model has this but my 57 has a short length of pipe that connects to the tank with a short rubber tube and then the steel part goes outside the cab and has the filler cap on the end. you could return the fuel through the filler neck. it is easily removed from the tank, doesn't require the tank to be removed from the truck, it is easily cleaned and welded to, you can install a piece of steel tubing which could be angled to send the return fuel down directly into the fuel tank. sort of u shaped so it doesn't restrict the filler but also directs fuel down instead of straight across hitting the opposite wall of the filler pipe.

just a thought. of course a weld in bung in the tank would be best but this would be something you could do yourself without fear of going kaboom.

[Katrina/10]

Just plug the return line on the fuel pump.

[chincha805]

i thought about that , but won't it create more pressure?

[Katrina/10]

It does not seem to make any difference. Honestly, I have never put a fuel pressure gauge on the line, but I have capped them off many times in the past with no problems.