Hi Folks
Has anyone added a return line to an OEM sender or tank? Looking for some suggestions.
Thanks FABO
Has anyone added a return line to an OEM sender or tank? Looking for some suggestions.
Thanks FABO
ADDING A RETURN LINE TO AN OEM NON-EVAP FUEL SYSTEM QUESTION
- Thread starter CFD244
- Start date
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Are you looking to add a vapor return or a fuel return?
I want to use a 3 line filter for a fuel return to reduce the chance of a fuel system vapour lock. Have a new 1970 tank and a used OEM sending unit. Building the car now.
A few sending units have a nipple on them either 3/16 or 1/4 not used ,capped. See if you can get 1 like that and run the return line to that. If not the return to the filler pipe works and can be a bolt in deal.
If there isn't, the hose or pipe could be run through a grommet in the floor. The pipe would have a 90 degree bend inside the filler tube and stick out of the tube on the tank end so as not to be spraying constantly on the grommet but into the tank. I'd look for the sender with the extra nipple first.
I have a new aftermarket sender with the nipple, but trying to use my original sender due to accuracy issues with aftermarket. Also, trying to avoid running fuel through the interior (trunk) of the car.
MadScientistMat
Well-Known Member
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Another option: Sump the tank and use the sender as the return. More effort than brazing a fitting to the sending unit but makes sense if you already need to deal with fuel slosh on a race car or EFI conversion.
TrailBeast
AKA Mopars4us on Youtube
I drilled the OE sender and used a brass lamp nipple and a nut on each side, then soldered a small section of copper tube to the brass piece for the line to slide onto.
A couple of nylon washers from Ace Hardware and it worked great.
Been that way for 5-6 years.
canyncarvr
Well-Known Member
I've got the same job on my 'to do' list. I'm considering this:
www.efisystempro.com
Note there is also a reference on the above page to a Holley part that has a similar fitment.
I don't know how much room there is on the OEM sender hat. Maybe there is room for either of the above, maybe not.
Originally, I figured to simply attach my return line to the vapor return fitting at the top of the tank. Seems that won't work as that tank 'hole' is designed with a separator INside the tank...not something you could reasonably dump fuel INto from outside. Sure is a handily placed nipple, though!
The 'universal fuel tank return' above is going to be a splasher. Much better, seems, to return the fuel as 'quietly' as possible...preferably UNDER the fuel level in the tank.
Fuel Tank Return Port Kit - Bulkhead Fitting
With few exceptions, all fuel pressure regulation methods for EFI systems require fuel to be returned to the tank. So if your tank does not have a return port on it then you're going to need what you see here. Earl's Stat-O-Seal's go above and below the hole and the 90-degree angled bulk
www.efisystempro.com
Note there is also a reference on the above page to a Holley part that has a similar fitment.
I don't know how much room there is on the OEM sender hat. Maybe there is room for either of the above, maybe not.
Originally, I figured to simply attach my return line to the vapor return fitting at the top of the tank. Seems that won't work as that tank 'hole' is designed with a separator INside the tank...not something you could reasonably dump fuel INto from outside. Sure is a handily placed nipple, though!
The 'universal fuel tank return' above is going to be a splasher. Much better, seems, to return the fuel as 'quietly' as possible...preferably UNDER the fuel level in the tank.
mopowers
Well-Known Member
Is that like a bigass rivnut? I've never seen one of those before. That's a damn good idea! Thanks for posting that.
Yes it is. When you tighten the bolt, it collapses the sleeve and traps the fitting.
67Dart273
Well-Known Member
^^You can also buy nut / threaded bulkhead fittings such as in JIC/ AN and after making a clean hole in a flat spot, you could reach a finger or two through the sender hole to tighten it up.
I silver brazed a tube in mine, but I hesitate to recommend that, explosion hazard. What I did, was to disconnect the tank vent fitting, and extend it upwards with a scrap tube. I drained the tank, and ran CO2 from my MIG setup through the fuel line and tank, and it vented out the cap, which I later installed, then continued to vent out the temporary tube. I lit it several times to see if the escaping fumes were flammable, and after a few minutes, it would no longer light. I ran CO2 in there for several more minutes.
I made a hole sort of above and aside the sender hole, not with a dril, but an awl, then used a tapered sheet metal awl to enlarge the hole, which of course leaves a big lip for more thickness.
Then silver brazed a scrap of tube in. Frankly, I still don't know for sure how safe that was, and have read CLAIMS of not good outcomes.
Here, threaded bulkhead connectors
I silver brazed a tube in mine, but I hesitate to recommend that, explosion hazard. What I did, was to disconnect the tank vent fitting, and extend it upwards with a scrap tube. I drained the tank, and ran CO2 from my MIG setup through the fuel line and tank, and it vented out the cap, which I later installed, then continued to vent out the temporary tube. I lit it several times to see if the escaping fumes were flammable, and after a few minutes, it would no longer light. I ran CO2 in there for several more minutes.
I made a hole sort of above and aside the sender hole, not with a dril, but an awl, then used a tapered sheet metal awl to enlarge the hole, which of course leaves a big lip for more thickness.
Then silver brazed a scrap of tube in. Frankly, I still don't know for sure how safe that was, and have read CLAIMS of not good outcomes.
Here, threaded bulkhead connectors
I have a friend who helped me with adding a return nipple to my 65 Valiant years ago. We removed the tank made sure it was completely empty and filled it up with water and he brazed it right on. I could have brazed it myself, but he's a danged artist and his welds looked slap factory. lol
If the tank is brand new and never seen fuel… a 1/8” pipe coupler (threads on the inside made to couple two 1/8” pipe ends together) can be drilled into the tank, positioned 1/2 way and mig welded.
I do this in the shop all the time. If worried about the weld - mix up some JB weld and neatly cover your weld.
We pressure check the tanks after we are done at my shop. That 1/8 will allow a 1/8” male pipe to 1/4” barbed adapter.
Easy piezy.
I do this in the shop all the time. If worried about the weld - mix up some JB weld and neatly cover your weld.
We pressure check the tanks after we are done at my shop. That 1/8 will allow a 1/8” male pipe to 1/4” barbed adapter.
Easy piezy.
Where is the best place to put it into the tank? Yes brand new tank...never seen fuel.
For a vent or fuel return I go to the passenger side of the sender. (Since your fuel lines are on that side. You can add your return line from the third port and run it along the factory line and make it look correct.Typically just above the sender height. But if you are below the fuel level the pressure in that third leg will overcome the tank static pressure. The higher the better on that front face.
Do you use a brass or metal 1/8 F/F fitting to go through the tank?
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