Hi all,
Could use a few good advises on how to create a return fuel line on my Pantera from 1974. Any good suggestions?
I would prefer to keep the car and fuel tank as stock as possible, so simple solutions are preferred if possible.
Eg would it for instance be possible to do it in Gas Tank Fill Neck with a standard Fuel Return Line Fitting?
Big thx in advance.
BR
Bryske
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Put one of those fuel filters from a ‘70s Ford Station Wagon with the fuel return right by the carb, and use the tap off to your return line.
Not sure where to plumb back into the tank, but the fuel overflow tube seems reasonable!
Are you upgrading to an EFI system? Most take the fuel from the bottom of the tank replacing the drain bung with a hose fitting and then use the stock supply line on the fuel sender as the return line.
Alternative is to use an in tank pump with built in pressure regulator/relief so no return line required.
The overflow tube is the tank vent, if you block that you will likely collapse the tank, you could remove it and fabricate a round plate to go in it;'s place and probably get a return line and a Jazz style rollover valve/vent in it.
Yes - true upgrading to Sniper EFI. Really would like to avoid changing anything on the fuel tank, because I would like to be able to go back to stock again if later wanted. That was why I was thinking about the fill neck solution.
My 1973 L model has a pipe plug on top of the tank. That was used as the fuel return line for my EFI system. When I was still using a carb on the car, I had a return line that was tapped into the gas tank filler neck.
On my '72-1/2 (#4460), I needed to replace the fuel gauge float assembly.
On my tank, the fuel pick up line is integral to the tank. It is an internally welded in steel tube in the tank, with no access to it for replacement. The tube had rusted through at about 1/2 tank level. That meant for me that if the fuel level went below that "rust hole", the engine would get no fuel.
So on a full tank of gas, the car ran fine. Once the level hit that hole, it would stave the engine.
The current replacement fuel level sender that is available for the Pantera also now includes the fuel tube pick up. So by replacing the sender/pick-up assembly, the original fuel line supply line from the tank became available for a return line.
That is the procedure that I would recommend to you for your current application.
The fuel line supply line will be a simple 3/8" fuel hose about 3" long and the banjo bolt and fitting can stay in place with a simple fuel line hose connection.
That's about as simple and stock looking as you can get.
There will be a "return line port" somewhere in your EFI system to connect to.
@panteradoug posted:The current replacement fuel level sender that is available for the Pantera also now includes the fuel tube pick up. So by replacing the sender/pick-up assembly, the original fuel line supply line from the tank became available for a return line.
That's the later style, which Bryske would likely have stock on his '74 as the fuel supply line, which eliminated the early style fuel line.
@bryske posted:Yes - true upgrading to Sniper EFI. Really would like to avoid changing anything on the fuel tank, because I would like to be able to go back to stock again if later wanted. That was why I was thinking about the fill neck solution.
With any of those options you really won't be modifying the tank in such a way that it cannot be simply reverted later.
As Julian suggested, the easiest way to supply and return fuel is by drawing fuel from the tank drain and returning it through the existing supply line.
B.A.T. in Florida carry Setrab high flow banjo fittings, which are perfect for the tank drain. If I recall, the size is M22 x 1.5. I used -8 AN fuel lines but my return is -6 AN.
To clearly answer your initial question, yes, returning fuel to the fuel filler neck would be an acceptable solution.
That approach was previously used on 2511 and I know it has been utilized on other cars.
Larry
Taking the gas tank drain plug out is not easy. The plug on mine was suck so hard that I could not get it out without risking damage to the tank. I actually ended up drilling the drain plug out. I have heard of some people damaging the gas tank when they tried to remove that drain plug. It is a great place to draw fuel out of the tank if you can safely get the drain plug out.
The trick I have heard on removing a stubborn drain plug is to use an impact driver set on a low force. Of course penetrating solvent is always the first step
A brute force attack using a long breaker bar runs the risk of actually tearing the fitting loose from the thin sheet-metal of the tank
Larry
Attempting to remove the drain plug is not for the faint of heart on a Pantera. I'd say that if it has never been out since new, then it is a 50/50 proposition.
50% chance that you get it out. 50% chance that you damage the tank/and or wreck the plug.
The other thing is that even with a banjo fitting on it, it is susceptable to road hazards. With a plug in it, it's fine. With ANYTHING that is attached under it, that attachment is vulnerable.
Your call, but it isn't really for a novice to attempt. You DO NOT want to unleash Godzilla with an impact wrench to attack it.
@lf-tp2511 posted:To clearly answer your initial question, yes, returning fuel to the fuel filler neck would be an acceptable solution.
That approach was previously used on 2511 and I know it has been utilized on other cars.
Larry
That’s the method Dennis Quella recommends. I believe he uses a 90° bulkhead fitting, pointing towards the bottom of the tank.
Bottom feed, protected behind a shield, pump on the lower frame rail, all hoses hidden behind the gas tank shield. This was for a carburetor. When I switched to EFI I put the high-pressure pump in the same location and had a return line plumbed to the original supply line.
t
Damn you, David. 😉
Now I have another project to put on my to do list
really like how you executed that shield
Larry
I took a similar approach with my fuel pump, secondary fuel filter and fuel pressure regulator. They are mounted on a heavy aluminum plate that tucks up between two frame rails. This serves to keep them away from any heat source and makes them very easy to access. My feeling is, the less "stuff" in the engine compartment, the better!
By the way, the fuel pump I'm using is the tried and true Bosch "044". It's cheap, available everywhere, quiet and easily supplies enough fuel for 650 Hp.
Thx alot for many super good suggestions - I really appreciate the help. :-)
I like the idea of using the drain-plug, but are scared if it will go wron trying to remove the drain-plug. I'm really all for keeping the old parts alive as long as possible. My carb has been changed many years ago before I bought the car and also the engine has had modifications, but the rest of the car is actually very stock. So won't like to break the gas tank.
As joules wrote, I can see my carb get's the fuel feed from the fuel sender pipe. See photo below.
And there's another hose going from the tank, which goes to the "Canister Assembly Fuel Vapor Storage" (blue can in the engine room in passagerside), see photo below.
I assume this hose to the "Fuel Vapor" I better keep, for the tank to breathe?, otherwise that could have been used as return line.
I got some inspiration from some youtube video and found Moroso kit 65385:
I was thinking, perhaps that was a easy way to install this in the Gas Filler Neck Hose, mine already looks like it's in for a replacement, see photo below.
But I'm not sure if it will fit in there, in the Gas Filler Neck, the billet aluminum adapter, what do you guys think?
Also I read somewhere, that it's "bad" to not have the return line done with a hose down into the tank, so the fuel gets dumped in the fuel in the tank and not dripping down creating bubbles on top of the fuel. Is this a valid concern? If yes, it would ruin the idea of added the return line to the Fuel Filler Neck, eg via the Moroso kit. :-/
Once again REALLY appreciate all the inputs, You guys are just super hero's. :-)
BR
Bryske
I'm sure you know this but that filler hose is looking rough. Age cracked.
It appears you have an extra bung someone has welded on top of the tank?
https://pantera.infopop.cc/top...65#22864114474758465
Yes, husker , that’s also why I wrote mine sseems to be in for a replacement. ;-)
Bryske,
You might be able to use the fitting that Julian pointed out, as your return. Yes, it's OK to let the fuel from the return, drain into the top of the tank. It's completely unnecessary to have a line that goes to the bottom of the tank.
I had no trouble at all, removing my drain plug. I used penetrating oil a few hours before I attempted to remove it, then gave it a couple of sharp blows with a hammer. I used a heat gun to get the drain plug warm, not hot! I then put my impact driver on it, at a very low torque setting. After about 30 seconds of hammering away, it was out.
Ok, davidnunn , actually sounds like it might be feasible for me to do. At least I could try it fairly gently and see if I can succeed with broking anything.
What fittings did you use for the drain-plug hole? - I'll bought them in advance then. Also buy the Moroso kit as backup solution.
Hi joules , what you do you mean? - not sure what "extra bung" you mean? Can you elaborate - thx.
@bryske posted:What fittings did you use for the drain-plug hole? - I'll bought them in advance then. Also buy the Moroso kit as backup solution.
I used a Setrab M22 x 1.5 high-flow banjo fitting with a -8 AN outlet. Setrab products are made in Sweden, so it's probably easier to find this in Europe than in the USA.
Also, the "extra bung" Julian referred to is obvious in two of your photos. It has an Allen head set screw threaded into it. Just remove the set screw and buy a fitting the same size. Just make sure it's large enough for the Sniper's return line. If you are going to use this bung or a return fitting in the filler neck, there's no need to draw fuel from the bottom of the tank. You can use the OEM fuel pickup.
Ahh, good point davidnunn , I now see it on the image. Got no clue why I didn’t spot it. I guess it was so focused on the two point where there was something already attached to the gas tank. Vapor and fuel sender unit.
As I know the car is very stock, I’m wondering what that has been used for? Can it be that it the “hole” for the original fuel suck pipe, but on later models (mine is a 1974), they used the same gas tank from the factory but just blocked it with an allen head?
Anyway, it looks like the obvious solution for me to use as return line, ✌🏻
@joules posted:It appears you have an extra bung someone has welded on top of the tank?
"Added"? That is the exact location of my original fuel "pick up". I will admit that it looks a little different then mine but I wouldn't rule out the original being replaced with a '72 used tank and that tank having a repair to it on the flange.
Take the plug out. If it has a tube in the tank going to near the bottom, then likely it is an original "early" tank. In any case it would make an excellent location to the return connection.
Yes makes sense. Do you - panteradoug - by any chance remember what the plug size was on your old fuel pickup? Thx.
Yes. I am using it for a fuel return now. It is a M10 x 1.0.
I'm using a banjo bolt with a -6 an male.
Chen Ying SI300600 Swivel Fitting Set M10 x P1.0
On yours you do need to remove the plug that is in there and match that thread. If there was repair work done and the bung was changed out it is unlikely to be the same size.
From here it does look like it is a 1/4npt plug.
