Idea for a long range fuel tank

[pete.sb]

Just throwing this out there -

I've been looking what it costs to have a long range/aux fuel tank installed in a GQ, I've spoken to a few shops and the idea I get is the same. The aux tank does not interface with the main tank, it has its own fuel line that you can switch from in the cabin. Like so

[main] - [aux]
|..............|
|_switch_|
|
|
{engine}


Well, what would be the problem with installing an auxilliary tank that just pumps fuel into the main tank??

So like...

[aux]
|
|(pump or something goes here)
|
[main]
|
|(stock fuel line)
|
{engine}


I'm just thinking that would be a whole lot easier (and cheaper) than installing extra pumps and line switches and an extra gauge etc.

[ISUZUROVER]

Plenty of people have done it that way. The disadvantage is that (a) you are relying on 2 different fuel pumps instead of 1, and (b) if you damage your main tank you are stuffed.

[thehanko]

The suggestion your suggesting is exactly what i plan to do as well.

would need to put a t piece or something into the return line on the main tank for pumping the fuel into.

The only issue with this that i can think of, is that you would need to run a second fuel guage for the second tank. where as with 2 tanks run separately when you switch the pick up the the aux tank, it should also change the fuel guage sender unit to the aux tank and now the same guage shows the level on the new tank your using.

but apart from that, i cant see much benefit.

[ddr]

The GU's run it that way & IMO it sucks for the reason below

if you damage your main tank you are stuffed.

If you can choose which tank you are drawing & smash the Main you can still limp home off the Aux tank.

[Jeff80]

The GU's run it that way & IMO it sucks for the reason below

if you damage your main tank you are stuffed.

If you can choose which tank you are drawing & smash the Main you can still limp home off the Aux tank.

So does the 80 series petrols, and I think 100 series too.

And Im with ddr, about the main tank getting damaged and being up that creek!

[bogged]

Well, what would be the problem with installing an auxilliary tank that just pumps fuel into the main tank??
.

Gu pumps from aux tank into main from factory.

[98lux]

100 and 105 series you can choose what tank you want as stated above.

[Patroler]

One advantage of pumping from the aux to the main and not having a 6 port valve on a diesel at least would be that you can totally drain the aux tank with the pump.
With the valve and being diesel you don't ever want to totally drain tanks before changing over, therefore you'd leave 10 litres or so in the aux tank that you couldn't really use, on top of the 10 litres that you'd want to leave in the main so as not to run it right out.
Therefore a transfer pump could let you have a little extra useable range.

Personally i'm not too worried about damaging the main tank - its just not something that happens that much (depending on where you drive)- and if it does, the outlets of the tanks aren't that far apart and you could rig the lines to feed directly from aux to engine.

Fwiw the pump or valve used in a lot of commercial applications can be purchased seperately on ebay a bit cheaper

6 port valve - made by pollak on ebay US
Transfer pump - Facet solid state - ebay AU - used by longranger
both about $100 delivered.
http://cgi.ebay.com/ebaymotors/POLLAK-6 ... 0256777005
http://cgi.ebay.com.au/FACET-SOLID-STAT ... .m20.l1116

[Chucky]

As said the petrol 80 series pump from the aux to the main. The diesels suck and return to the same tank witch is switchable.
I prefer this method myself. You can get 3 way solinoids (one for suction and one for return) quite cheap as well. As for pumps you'd only need one, put the suction solinoid in the pumps intake side.
In my diesel I run one tank dry before switching over, unless doing so is dangerous. When I loose power I just switch the tanks turning the engine over on momentum, she normally bleeds itself then just keeps going. If it does stop, I just turn it over a few times and it'll bleed itself.