I need a little guidance from the experts on how to fabricate a new fuel tank system with my shooting brake project.

It seems like I have multiple options for a fuel cell, I'm thinking of reusing the stock pump mounted in spare tire well along with the fuel cell.

-Any advantage to using a fuel cell with integrated pump? (A lot more expensive BTW)

-Why are three metal lines running from vapor separator into the stock tank?

-Can I substitute something else for the stock vapor separator?

-Can I combine those three lines into one and simply dump back into fuel cell?

Thanks!!

 

Three lines -
1) fuel from tank to separator, AKA swirl tank.
2) from swirl tank to fuel pump.
3) vapor from the swirl tank back to the main tank.

 

Most similar fuel systems do without the tank. Fuel flows from the main tank to the pump. I do not believe the swirl tank is necessary, it seems to be just a big pre filter for the fuel.

 

The swirl tank is there to ensure that you don't lose suction when the tank is very low and you are cornering hard.
Not that anyone would ever drive a Jag like that of course, that is the preserve of oicks and boy racers.

 

In tank pumps are much quieter, run much cooler and typically don't need surge tanks like the XJS has/had. The XJS had a surge tank due to the wide design of the original tank, it would easily expose the intake port on hard, sustained cornering. As Jaguars were designed to be driven, and driven hard, this was an issue.
If you run an intank pump, you could probably scrounge a tank off some other application, it will have the pump, sender and return lines in one easy to fit removable assembly.
All a new fuel tank will need is fuel out, fuel return and a vent hose, ideally to the carbon canister.
With what you are doing, I'd be tempted to put the tank on one side of the old recessed boot floor and battery/tools etc on the other side. You'd be able to link up to the old fuel lines pretty easily from there and the filler should be able to snake it's way down and not take up much, if any, interior space.

 

Thanks for insights.

Does it matter how vapor separator hoses are hooked up? Can the three lines connected to the tank be combined into one?

 

Unfortunately no. You need a separate fuel feed and return line. The vapour line from the tank is usually at the highest spot on the tank, usually in a dome that prevents being blocked by liquid fuel.
Plenty of high quality rubber lines available to let you run lines to the existing outlets in the body.

 

Someone above may have misunderstood your question about the vapour separator. If you do mean the little thing above the RHS top corner of the tank, you can do away with it. I suggest you just fit a modern inline breather valve to the tank, this lets out any excess pressure and lets in air to prevent any excess vacuum inside the tank. You can use one of the vapour separator spigots on the tank for this and conduct the line to the outside.

The line MUST go to the outside, not back into the tank.

Fitting in the fuel tank to the model will be a bit of a challenge, as will getting one large enough. I have a vague feeling that the Eventer used round tanks under the decking. An intank pump will be hard as the tank(s) will necessarily be round and flattish. I think that a "swirl pot" will be needed for the tanks to drain into, so there is a continuos supply of fuel on corners, braking etc, and either an intank pump fitted into the swirlpot, or an inline pump immediately downstream of it.

greg

 

I think you're right about the misunderstanding. It looks like the stock fuel vapor separator runs back into the engine which I expect is for emissions reasons (I can live with altering this). I appreciate your insight on how to vent aftermarket tank...