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Hi experts,

My 1978 spider had a carburettor conversion [from injection) by previous owner... Ive just discovered that there are still two fuel lines running to the engine bay from the tank; 1 is in use via the fuel pump to the carbs, the other is just open ended and terminates under the car !!!! This could be where the strong smell of fuel is coming from. it is still connected to the fuel tank. I know this because I stupidly sucked on it to see if there was any fluid /air in the line. The result of this test was predictable. Anyone know what is the correct fix for this second (redundant?) fuel line... Im concerned that If I just plug it up the fuel tank may not vent properly.... Whilst tracking the fuel lines from the tank I discovered more inlets / outlets than I thought I would find... can anyone tell me what each of these access points to the fuel tank is for? The fuel is currently sucked { by the aftermarket electric fuel pump) from the access point marked A in the photo. access point B has been terminated by a previous owner. Access point C is the line that terminates, unsealed at the engine bay underneath the steering box, and access point D goes to a black tank adjacent to the tyre jack,( any. idea what this is?? see photo 146, it has an outlet of a 1/4 inch OD line that disappears to an unknown location, but is clearly fuel related. )

(Yes, know the steering box is leaking, that is why I was under the car when I discovered the strange fuel line floating in space not doing anything. )

I found some really useful posts by other BB'ers that told me there was a recall for this vehicle back in 1982. this recall was to install the in tank fuel pump. I think my spider has this recall work done, but my question now is that two electric pumps working in series seems like really bad idea? the vehicle runs ok, but I would like to work out what is going on with all these fuel lines/ ports. I would much prefer to use just one fuel pump, not two.

Im also concerned about venting... what is the correct means of venting the tank as fuel is sucked out?

any help would be really appreciated.
1681124
) ( and yes, I
1681123

many thanks....
 

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On a Spica car one line brings fuel from the supply pump, the other takes the excess back to the tank from the injection pump. You can cap off/remove the one not needed. It goes from the FI pump through the filter head to a fitting on the driver's side of the tank, left front top of the tank, to dump back in. It is a hard line for most of its length, rubber hose at each end.

You still have the large filter in the engine compartment? You do away with that too, run a regular small filter.

Andrew
 

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You still have the large filter in the engine compartment? You do away with that too, run a regular small filter.

Andrew
succint!
 

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Are you using a fuel pressure regulator?
The previous owner of my previously-SPICA 1972 kept the original fuel pump setup and to- and return-lines.
He ran the lines into a "Y" that went into a fuel pressure regulator (with pressure guage), and then out into the carbs. The Y had the return line as well as the feeder line from the tank, so any excess gas just routed back the other branch of the Y to return to the tank.
Pretty neat setup actually.
If interested, I can post a pic of the engine compartment.
 

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1982 Alfa Romeo Spider Veloce, 1997 BMW M 3/4/5, 2007 Land Cruiser
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In my 1982 Bosch FI, many of these components are there. The black canister by the jack is part of your tank vent/vapor recovery system. It doesn’t handle liquid fuel, vapors. That in-line silver thing is a one way valve, and the other little thing on the end of the short T is a check valve to let atmosphere to the system. The plastic line goes forward to a charcoal canister hidden behind the passenger wheel well. The charcoal canister draws vapors from the trunk, then scrubs them before returning them to the intake manifold. The two lines that go to it wrap around your OVS and exit high up on the inside rear fender of the engine compartment.

You can find plenty of info on all this here on the forum. I rebuilt all this plumbing, and with a new OVS, smoke test to eliminate all vacuum leaks, my car is running like a dream right now. First spring ever!
 

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Discussion Starter #6
Great info... thanks all.
Stasha, I would be very keen to see the Y junction and pressure regulator setup.... lots of threads here I have read seem to have fuel pressure (too much & too little) as a central problem. I would like to get mine right. I am running Delortos. Not sure what the prescribed inwards pressure is for these carbs, but Im sure I can find out.

Down here in Australia our EPA are not overly concerned with emissions. I know reducing harmful emissions is good for all of us, but it has not yet been legislated against. Thus, I would like to remove the charcoal canister and tank vent/vapor recovery system. Simple is good in my world. The less stuff on board, the less to go wrong. I would prefer a simple free vent on my fuel system, unless there are good reasons why all the complex arrangement is necessary?
A small after market filter has been fitted immediately upstream of the carbs. Filter is clean which gives me a good indication of the status of the fuel tank.
 

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Stasha, I would be very keen to see the Y junction and pressure regulator setup.... lots of threads here I have read seem to have fuel pressure (too much & too little) as a central problem. I would like to get mine right. I am running Delortos. Not sure what the prescribed inwards pressure is for these carbs, but Im sure I can find out.
...
Here it is.
I moved the fuel pressure regulator to the firewall, handily fitting into the windshield washer reservoir bracket (I bent the base of the reservoir bracket around the regulator bracket). Had to move the reg because I was installing an airbox which interfered with the reg's original location at the front right side of the engine compartment -- and the airbox also required relocating the washer reservoir.
Reversed the feed into the Webers, changing it from front-to-rear, to rear-to front carbs.

It's a Holley regulator and a VDO gauge.

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