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Old 01-07-2016, 01:04 PM   #1
gable74
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Fuel Tank / Aux tank(s) question

Is it safe to say that I could tie my two saddle tanks together and use them as one tank since they sit at the same level in the truck? I am considering going with an electric tank selector that would switch tanks and switch fuel sending units at the same time but they only make them for dual tanks, nothing for three tanks.
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Old 01-08-2016, 07:25 PM   #2
motorcritter
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Re: Fuel Tank / Aux tank(s) question

Your running the in-can tank, plus two sidesaddle tanks, I'm assuming. Linking the side tanks to a common outlet, running the stock tank into your switching setup should work, but only one side tank level gauge would be needed. A pretty robust side tank link pipe would help keep the tanks fuel levels constant. Treat the side tanks like one tank, the stock one like the second.
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Old 01-08-2016, 07:54 PM   #3
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Re: Fuel Tank / Aux tank(s) question

Can you tie them together at a low enough point to be useful and still be safe though? Fuel doesn't flow uphill, so the line needs to be the lowest part of the tank (or it'll be the lowest point at which the two tanks will exchange fuel, anyway).

I worry that having a line come out of the bottom of one tank and into the bottom of the other would be so low that it'd be hard to route safely. But I can't read your mind or see the tanks, so just throwing it out there.
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Old 01-08-2016, 09:21 PM   #4
jeffahart
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Re: Fuel Tank / Aux tank(s) question

Those old saddles don't have sending units. Engine sputter is the gauge, plus a little horse sense on when you filled and how long you've drove on the particular running tank. Just keep them isolated. I drove thousand of miles with my old saddles back in the 80s. Just reach down and flip the fuel petcock when the engine starts to sputter. I recently ditched my old saddles. Had mixed feeling about them for my usage now days.
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Old 01-08-2016, 10:07 PM   #5
mtdave2
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Re: Fuel Tank / Aux tank(s) question

Well my aux tank has a fuel sending unit in it, and it is orginal..

The two tank thing, I would just tie the outlet hoses together and run to an electric tank selector, one for main one for aux tanks.
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Old 01-08-2016, 10:08 PM   #6
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Re: Fuel Tank / Aux tank(s) question

What's your goal in tying the tanks together in a manner that's different from the current arrangement? My 72 GMC has OEM sending units for the dual aftermarket tanks (Travel Tanks) with a toggle switch to select the sending unit for either aux tank or the factory tank (fwiw pic here: http://67-72chevytrucks.com/vboard/s...48&postcount=3). A floor mounted selector allows you to manually select gas flow from your tank of choice.
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Old 01-08-2016, 10:13 PM   #7
jocko
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Re: Fuel Tank / Aux tank(s) question

Like mentioned above, some saddles had senders, some didn't. All NL2s had senders. I think I'd avoid tying them together - like Pete, I'm not sure how it's any less work, unless you had a single damaged inlet on the tank selection valve (in which case I'd really want to replace it anyway). Seems if your answer is "it should work" and there's no more work in doing it the original way - I'd go with original because we know it works. Personally, I'd prefer to switch at the valve and have the pump drawing fully from ONLY the tank I've selected rather than two that feed into it. Again, I agree it should work, just don't see what there is to gain by linking them before the valve - unless perhaps the goal is just to avoid one additional flip of the switch.
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Old 01-08-2016, 10:24 PM   #8
89AKurt
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Re: Fuel Tank / Aux tank(s) question

I removed the saddle tanks off my truck, if anyone in Arizona wants cheap tanks, let me know.
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Old 01-08-2016, 10:30 PM   #9
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Re: Fuel Tank / Aux tank(s) question

If I still lived there, I'd be on my way... Bedside or wheelwell filler neck?
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Old 01-08-2016, 11:17 PM   #10
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Re: Fuel Tank / Aux tank(s) question

Quote:
Originally Posted by jocko View Post
If I still lived there, I'd be on my way... Bedside or wheelwell filler neck?
Wheelwell.
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Old 01-08-2016, 11:42 PM   #11
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Re: Fuel Tank / Aux tank(s) question

those are the BEST! Someone's gotta come grab those. Holy cow.
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Old 01-09-2016, 01:42 AM   #12
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Re: Fuel Tank / Aux tank(s) question

I guess my only real reason was because I'm lazy... What I wanted was the convenience (or the simplicity) of flipping one switch that would control both the tank selection as well as the sending units. Yes, both of my aux tanks have sending units. I have the valve on the floor as well as this switch on the dash that selects the proper sending unit. The green switch controls the cruise control and has nothing to do with the fuel tanks. Just gauging the thoughts of those who certainly have more experience on the matter than I do. Thanks for the input!
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