2 gas tanks on 1 gas gauge?

wantatlc · 03-27-06, 12:52 PM

I asked this question deep in another thread, but it got no play becuase of it I think so I thought I would ask it on it's own.

if you ran both + leads from the sending units on 2 different tanks (your main and the auxillary) to a 2 position knob and then from said knob on to the + post on the after market gas gauge on my dash that is currently setup to read only the main tank, could you not then turn the knob and switch between readings from 2 tanks? NOTE: both tanks would use the same brand/style sending unit made to work with the same style/brand gague on my dash so perfect compatability.

can anyone with good wiring knowledge confirm if it is infact as simple as I think it is logically and just adding a turn knob inbetween the gauge and both sending units to make it possible to flip flop between 2 tanks on 1 gauge?

if it is possible.. I believe I need a SPDT (single pull double throw) switch that has 3 posts (1 for each tank and 1 to gauge) and is always on (on-on) and has no off option. that is, the switch is either A or B and no dead center. correct?

andrewfarmer · 03-27-06, 12:55 PM

correct

wantatlc · 03-27-06, 12:59 PM

much appreciated

hi50phd · 03-27-06, 01:43 PM

And, if both sending units match your guage.

wantatlc · 03-27-06, 04:45 PM

Quote:

Originally Posted by hi50phd

And, if both sending units match your guage.

guess you missed this:

"NOTE: both tanks would use the same brand/style sending unit made to work with the same style/brand gague on my dash so perfect compatability."

hi50phd · 03-27-06, 05:39 PM

So, will you be using and aftermarket guage?

wantatlc · 03-27-06, 06:40 PM

yes sir.

I already use an aftermarket JC Whitney gauge and sending unit kit for the front tank as the original one is dead and I could never get the gauge to work. So, I have ordered the same exact JC Whitney sending unit/gauge kit for the rear and will just not use the gauge and use the gauge I already installed.... so 1 gauge on the dash only.

should be kind of slick when complete. if your really interested in what started this whole thing read here....

and this is related as well

hi50phd · 03-28-06, 03:41 AM

just wondered if you'd found a Unicorn, the mythical 17-130 aftermarket sender.

Rick '79 FJ40 · 03-28-06, 09:25 AM

My brother's 76 Bronco had a setup like you are talking about from the factory. The really slick thing to do is to get a solenoid-operated tank select valve and a double-pole switch so you will actually switch tanks when you switch gauges...

I know you can order these type valves for the Bronco. If you want to, check out Wild Horses webpage for those valves. www.wildhorses4x4.com

The biggest problem with switching the gauge like that is you can lose track of which tank you are running on and be looking at the fuel level in the wrong tank. My brother ran out of gas a time or 2 like that. The electric valve would prevent that.

wantatlc · 03-28-06, 09:42 AM

Quote:

Originally Posted by Rick '79 FJ40

My brother's 76 Bronco had a setup like you are talking about from the factory. The really slick thing to do is to get a solenoid-operated tank select valve and a double-pole switch so you will actually switch tanks when you switch gauges...

I know you can order these type valves for the Bronco. If you want to, check out Wild Horses webpage for those valves. www.wildhorses4x4.com

The biggest problem with switching the gauge like that is you can lose track of which tank you are running on and be looking at the fuel level in the wrong tank. My brother ran out of gas a time or 2 like that. The electric valve would prevent that.

I would like that system you mention and even looked at them. BUT, in a link above about my dual tank setup, I already have a hand mechanical switch in place to change tanks. So, that is why I just went the $4.00 switch route as I like the system I have and could not afford to go that route.

BTW, I actually installed the switch last night to tank 1 on my dash and have it hooked up and working just waiting for tank 2 to be attached in the coming weeks after I add the sending unit (see above link). And, I labeled the switch MAIN and AUX so I will know exactly which tank I am looking at. Also, you need to turn on an auxillary electric pump to help pull fuel from the rear tank to the engine, so that toggle (which has a light) is also a reminder of what tank you are drwing on. So, I think I am good there and no confusion shoud ensue.

45Kevin · 03-28-06, 10:21 AM

I had a 92 f150 with the dual tank setup. It was great on long trips to get 600 miles between fills. The system had one switch on the dash that changed from one sending unit to the other and at the same time flipped a valve where the two fuel lines converged. It was seamless.

Rick '79 FJ40 · 03-28-06, 01:50 PM

Quote:

Originally Posted by 45Kevin

I had a 92 f150 with the dual tank setup. It was great on long trips to get 600 miles between fills. The system had one switch on the dash that changed from one sending unit to the other and at the same time flipped a valve where the two fuel lines converged. It was seamless.

Yes, its a good system. The only drawback on my brother's Bronco was that the 2 tanks capacity together was about what a single tank holds on most 1 tank vehicles, 23 gal. I think the dual tank in this particular case was more of a gimmick than a real benefit...

Rick '79 FJ40 · 03-28-06, 01:56 PM

Quote:

Originally Posted by wantatlc

I would like that system you mention and even looked at them. BUT, in a link above about my dual tank setup, I already have a hand mechanical switch in place to change tanks. So, that is why I just went the $4.00 switch route as I like the system I have and could not afford to go that route.

BTW, I actually installed the switch last night to tank 1 on my dash and have it hooked up and working just waiting for tank 2 to be attached in the coming weeks after I add the sending unit (see above link). And, I labeled the switch MAIN and AUX so I will know exactly which tank I am looking at. Also, you need to turn on an auxillary electric pump to help pull fuel from the rear tank to the engine, so that toggle (which has a light) is also a reminder of what tank you are drwing on. So, I think I am good there and no confusion shoud ensue.

You did a nice job on the switch. I'm kind of a fanatic about labeling things and making them look "factory"...

wantatlc · 03-28-06, 02:05 PM

Quote:

Originally Posted by Rick '79 FJ40

You did a nice job on the switch. I'm kind of a fanatic about labeling things and making them look "factory"...

thanks.. see this post for more like that simple and clean and I can replace easy and cheaply.

this switch went into the hole for the "Fan" as I had no use for it.......

wantatlc · 04-09-06, 06:25 PM

UPDATE: success today. I hooked up the second sending unit I bought to the switch and did in fact confirm I can flip back and forth between the 2 tank sending units with a SPDT switch and use 1 gauge.

sweet setup.

DSRTRDR · 04-09-06, 10:39 PM

man, you're on a roll........

will we see the rig at Cruise Moab?

wantatlc · 04-10-06, 08:10 AM

I would like to but I have a big local race on May 7th (and I won the series last year) so I need/want to show up as that is my first love.

And, I have spent about 10 years or so going to Moab mountain biking everything there is to ride (and know how burley some of those trails can be) and I could easily see myself over extending my abilities.. getting caught up in the moment and frankly... I think I need another year of local wheelin to feel truly comfortable with the rig and my abilites before I tackle the trails at Moab I would want to tackle. Yeah, I could do the softball trails, but that is a long drive to do the easy stuff.