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Adding outlet to fuel tank
Banana - 23/4/17 at 01:07 PM

I need to add a new outlet at the bottom of my fuel tank, as currently my bike pump is having to lift fuel up out of the top. Which is not ideal for a gravity fed pump.

Are there any acceptable means of adding an outlet that doesn't involve welding?

Should add its an ally tank.

thanks

[Edited on 23/4/17 by Banana]


theconrodkid - 23/4/17 at 03:27 PM

i have one from an aircraft fuel tank in my clammy little hand,outlet is 11mm,comes with the rubber grommet.
no idea how much it was as aircraft laws have now changed and you need a filter so no longer available at stockist.


40inches - 23/4/17 at 10:13 PM

I used one of these, when I converted to EFI.


Banana - 23/4/17 at 10:25 PM

Seems to easy.. I guess that is what conrodkid was talking about.

No problems with it i take it?


theconrodkid - 24/4/17 at 07:04 AM

about the same as 40 inches says,but mine is straight


40inches - 24/4/17 at 08:59 AM

quote:
Originally posted by Banana
Seems to easy.. I guess that is what conrodkid was talking about.

No problems with it i take it?


Not so far
If you have a feed and vent already on your tank, use the original feed, the vent for the fuel return and the Aviation connector for the vent?


Banana - 24/4/17 at 11:19 AM

Not sure i follow, I have a vent and outlet/pickup on the top.

I need to add an outlet at the bottom to help my gravity fed pump.


40inches - 24/4/17 at 11:45 AM

Ah! I thought you were converting to EFI
The bike pump will be fine lifting from a top mount dip pipe, as long as the pump is mounted low down.
Some have mounted the bike pump on the engine cradle near the carbs, without problems.
This was how I did it. 3000miles without a problem
Fuel pump mounting
Fuel pump mounting


[Edited on 24-4-17 by 40inches]


Banana - 24/4/17 at 12:52 PM

That is a very good point, some folk have their pump located in the engine bay..
Although they may well have the outlet on the bottom of their tank, so still getting the pressure of gravity behind it.

My pump is lower than the tank, but he has to suck about 2ft upwards before getting down there, as a result my fuel filter is never really full (approx 1/8th full)
So it can't be right as a bike pump is gravity fed, at the very least the pump is working its nuts off.

The car does run like this, but im in two minds what to do with it now.

(I didnt noticed this was Fuel injection section... Doh)

[Edited on 24/4/17 by Banana]


40inches - 24/4/17 at 01:35 PM

quote:
Originally posted by Banana
as a result my fuel filter is never really full (approx 1/8th full)
[Edited on 24/4/17 by Banana]


Same here! On both the pre-pump filter, and pre-carb filter. It bothered me so much I manually filled
both filters with fuel. Next time I looked they both were back to nearly empty! lol


Banana - 24/4/17 at 01:42 PM

So surely on full throttle the carbs will be gulping in air?
I take it you didnt experience any probs 40?

Would be interested to hear some other views on this.


40inches - 24/4/17 at 01:58 PM

quote:
Originally posted by Banana
So surely on full throttle the carbs will be gulping in air?
I take it you didnt experience any probs 40?

Would be interested to hear some other views on this.


Never a problem. Looking at the filters when engine was running, I could see the fuel flowing through them.
Have you ever run the float bowls dry of fuel? It takes forever


Banana - 24/4/17 at 08:26 PM

Thinking about it.. As my pump is below the tank, once the pump has started to suck, there should be a siphon effect which should prevent the pump having to work too hard..

Im struggling to envisage how i wouldn't be getting air into the system though, seeing as my inline filter is so empty most of the time, especially when cornering.


40inches - 25/4/17 at 08:34 AM

Logically the air remains in the filters, its lighter than petrol
If any gets sucked into the fuel lines, it will end up in the float bowls, and by design they have air vents


Mash - 5/6/17 at 08:53 PM

Sorry to steal this thread, but I have a similar problem, except that I have an outlet at the bottom of the tank, but it is at front left, and is fouled by the link across my de dion, so I want to move it to the left side.

Would one of those connectors be safe enough to do the job do you think guys?

Plus, what's the best way to seal the existing outlet?

thanks in advance