Getting more fuel out of gas tank

[Guest ratchethack]

That leaves the fuel pressure regulator without a mounting point.  If mounted to this "left side mainfold", FI return-side fuel is placed in the left side compartment of the fuel tank, which I suppose is non-critical now that there is drainage from the right side.

If I'm following you correctly, this means the return fuel circuit doesn't include the tank. I b'lieve you need the tank in the circuit to take advantage of the heat sink that the tank provides, or you're headed for vapor lock???

[BrianG]

One last consideration in this "T"ing of the source-fuel line concept..............

 

Does anyone have any concern with the possibility that the fuel pump will suck air from which-ever side the return-fuel is NOT returning to, once that side is depleted?

 

Obviously, the FI return-fuel side will remain the fuller of the two.

 

This was not a problem with carb'd set-ups because it was all a gravity feed system with a very low flow rate.

 

I'm not quite so confident about the FI low requirement.

[BrianG]

If I'm following you correctly, this means the return fuel circuit doesn't include the tank.  I b'lieve you need the tank in the circuit to take advantage of the heat sink that the tank provides, or you're headed for vapor lock???

90347[/snapback]

 

No.. this "manifold" of mine is the regulator mounting point.... regardless of which side it goes on. It is simply a block with 2 holes opening into the stock fuel tank opening. It is essentially a "T" between the return-fuel and the supply fuel using the fuel tank as a plenum for precisely your reason..... mixing cool fuel with the return fuel.

 

Also, the regulator requires a solid mounting point..

[dlaing]

Does anyone have any concern with the possibility that the fuel pump will suck air from which-ever side the return-fuel is NOT returning to, once that side is depleted?

90348[/snapback]

The two sides should balance out, and it should not suck air until just before empty.

If I understand your design correctly, I am concerned that when you change air filters, etc., it will have a difficult time purging the air in the system as it MAY recirculate the air.

[Guest ratchethack]

Does anyone have any concern with the possibility that the fuel pump will suck air from which-ever side the return-fuel is NOT returning to, once that side is depleted?

I had the same thought, Brian. But I'm about as sure as I can be that this isn't a potential problem. Ambient air pressure is equal within the tank, so unless you're creating a high point in the fuel line on one side, gravity would ensure that there would never be an opportunity to suck air as long as any amount of gas is available.

[BrianG]

I had the same thought, Brian.  But I'm about as sure as I can be that this isn't a potential problem.  Ambient air pressure is equal within the tank, so unless you're creating a high point in the fuel line on one side, gravity would ensure that there would never be an opportunity to suck air as long as any amount of gas is available.

90359[/snapback]

 

Yes, that was my concern....will the return-side end up significantly higher (fuller) than the other side due to the constant FI system flow??

 

If this is a potential issue, it might be worth it to have the source and the return on the same side........ which is doable, but a plumbing challenge.

[BrianG]

The two sides should balance out, and it should not suck air until just before empty.

If I understand your design correctly, I am concerned that when you change air filters, etc., it will have a difficult time purging the air in the system as it MAY recirculate the air.

90356[/snapback]

 

The manifold/tank interface will be the same diameter as the tank-entry hole. I doubt that purged air would be sucked back, but it'll be something to watch for.....

[Guest ratchethack]

Yes, that was my concern....will the return-side end up significantly higher (fuller) than the other side due to the constant FI system flow??

It's another facet of the same principle.

 

IMHO, as long as fuel flows downhill , there wouldn't be a problem.....

 

I'd like to get started on mine right away - just as soon as y'er done with the "Proof of Concept".....

 

So - you making yours up this weekend??

[BrianG]

It's another facet of the same principle. 

 

IMHO, as long as fuel flows downhill , there wouldn't be a problem.....

 

I'd like to get started on mine right away - just as soon as y'er done with the "Proof of Concept".....

 

So - you making yours up this weekend??

90390[/snapback]

 

I'll get on it as soon as it snows! Riding season is tragically short enough here in the Great White North, as it is.

 

I don't need no wrenchin' gittin' in da way of da ridin'!