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1Back to top Go down   Plumbing in an Auxiliary Fuel Cell Empty Plumbing in an Auxiliary Fuel Cell Tue Apr 28, 2009 8:00 pm

pisano9

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86 K100RT
I need a little more range. I am considering adding a 2 gallon fuel cell. Some I see are gravity feed. Some have a small pump. Pro's or Con's?

Also where to I plumb in the fuel line into the fuel injection loop?

Anxious to hear what works and what doesn't, any suggestions will be appreciated

Thanks,

Kevin

    

K-BIKE

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Hi Kevin,
Off the top of my head a few points, to state the obvious to get gravity feed you need for the fuel cell to be higher than the minimum level in the main tank and you then plumb into the return line to the tank from the fuel injection system where fuel that is excess to requirements is returned to the fuel tank. Pros are simplicity and no wiring changes, cons are the centre of gravity is high and there is less flexibility in where you can mount the fuel cell.

If you put another pump in just for the fuel cell then you are no longer bound by the requirement for the position of the fuel cell to be above the minimum level of the main tank. You will also need a non return valve so fuel goes only from the fuel cell through its pump and up into the main tank through the same connection as the gravity feed option. The auxiliary pump will need to be chosen so as to be able to handle the duty required of it. The pros are the positioning is flexible, you are not constrained by the relative levels between the two tanks and the cons are greater cost and extra power wiring to run the pump plus some switch mechanism to operate the pump.
Regards,
K-BIKE

    

3Back to top Go down   Plumbing in an Auxiliary Fuel Cell Empty Re: Plumbing in an Auxiliary Fuel Cell Wed Apr 29, 2009 12:02 pm

pisano9

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Thanks K-BIKE, is the return hose the one that is forward on the injector rack?
Appreciate the help and think I will go with the pump.
Kevin

    

4Back to top Go down   Plumbing in an Auxiliary Fuel Cell Empty Re: Plumbing in an Auxiliary Fuel Cell Fri May 01, 2009 11:49 pm

scottiesharpe

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Can you plumb into the pressurized return line????

Won't that pressurize the aux tank???

Doesn't sound like it would work to me.

I think you need a non pressurized line to link the two fuel tanks.

    

pisano9

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I dunno...hence the question...thanks will look further
K

    

K-BIKE

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Hi Kevin,
The line to plumb into is the pressure bleed off from the fuel pressure regulator which goes back to the tank, that line should be low pressure whereas the rail lines are at about 36 psi from memory.
Regards,
K-BIKE

    

7Back to top Go down   Plumbing in an Auxiliary Fuel Cell Empty Re: Plumbing in an Auxiliary Fuel Cell Tue May 05, 2009 11:32 am

pisano9

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Thanks, K-bike. I will be exploring this weekend and will try to locate that hose. Gotta install my new sending unit and hope the fuel gauge works. So may plumb in the connections and valve, stub out the hose while I am in there, That way I only have to connect when I figure out the rest of it. Thanks Again for the help.
KC

    

scottiesharpe

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Beware - The return line is also under pressure, albeit less than the supply line.

    

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