Fitting a Second Fuel Tank

[Spinal]

Here's a question...

How does a second fuel tank get connected?

I.e. does it need it's own petrol pump, or is there a way to link it to the primary tank? Is it just gravity fed to the main tank?

Anyone with some experience in the area willing to give me a primer?

Trying to decide if it's worth doing (will use 1500 litres of fuel in a 3-4 week time slot soon), and will probably not be able to fill jerry cans in some countries.

M.

 

[whitenemesis]

IIRC don't older Landrovers have a change over switch for their aux tanks? Must be the easier way to go, fit a second fuel pump with the aux tank.

 

[Ted]

The older Jags certainly had two pumps with a changeover switch.

 

[bolide]

Is it just gravity fed to the main tank?

That's the easy way. However, if the pipe linking the two fails, the entire contents of the top tank empties into the car

Two tanks, two pumps, two filters, two non-return valves and two switches is what I'd recommend. If there's a return from the engine bay then it can return to the main tank

If the car might overturn, make sure both fillers are air-tight and provide breathers that can't leak if the car is inverted

You'll find everything you need in the Demon Tweeks catalogue

Nick Froome

 

[Giantvanman]

IIRC don't older Landrovers have a change over switch for their aux tanks? Must be the easier way to go, fit a second fuel pump with the aux tank.

Some; Military Lightweight and converted (i.e. additional tanks added) for expedition, for example.

 

[guydewdney]

My camper truck has two tanks. I connected both feeds to a changeover valve (actually a pneumatic valve) and the return to a similar valve, so i can 'take' from either tank and return to either too. You will need a second gauge.

 

[Timster]

What cars it for?

I'm breaking a 210 220 Cdi - still have fuel pump and associated paraphernalia if any help?

 

[Spinal]

Thanks - forgot to reply sooner!

The car is a nissan micra k11.

I'm thinking jerry cans will be the way forward for most countries, and hope the best for Turkmenistan (where we can't fill jerries). Too complex to have a second pump/switch...

Maybe moving the tank, replacing the back seats, and putting a single, bigger tank.... hmmmm

M.

 

[nb_racing]

Thanks - forgot to reply sooner!

The car is a nissan micra k11.

I'm thinking jerry cans will be the way forward for most countries, and hope the best for Turkmenistan (where we can't fill jerries). Too complex to have a second pump/switch...

Maybe moving the tank, replacing the back seats, and putting a single, bigger tank.... hmmmm

M.

Personally I'd be worried about safety, having a big fuel tank in the car with no bulkhead between me and it...

A safe ATL tank would cost thousands.

Any possibility of fitting a bulkhead behind the drivers seats?

Does the car have a spare wheel well? could you fit a tank in that?

Personally I'd go 2nd tank with fuel pump, filter etc, switchable and separately fused, this way you at least have a back up system if one pump fails. You could also fit a cheeky little transfer pipe, T'd off from the pump incase one pump does fail, then you can transfer fuel from one tank to the other.

Edit: 2nd tank would be 100 litres max, with some kind of bulkhead.

Also worth thinking about all that weight of carrying the fuel. It gets heavy...! I think 50l is 35KG ish? (I stand to be corrected.)

 

[Bellow]

Bag tanks are cheap secondhand. One from a Formula Ford will hold 2.5 gallons and will be shaped for behind seat fitment. One behind each seat will add 5 gallons of capacity.
If the Micra has its fuel pump external to the tank and the bottoms of all tanks can be arranged at roughly the same height then merely tee the additional tanks to the fuel line from the main tank upstream of the pump.
Any filler neck lower than another will need to seal (ie non venting) and that tank(s) filled first and vented higher than any tank's neck. It can be done as simply as that - if the pump is external...

 

[tim.100]

I think Jet A1 is 1242 litres to the tonne. Petrol won't be hugely different. I'd be very cautious about having petrol inside the car. There's many reasons for the Army & expedition vehicles to carry it outside!

 

[guydewdney]

There are connector thjngs for jerry cans to run generators, its a 'new' cap for the spout with a tube. Sealey JCA2 Double Tube Jerry Can Adaptor - Auto - Vehicle Products, Garage Equipment, Water Containers & Fuel/Jerry Cans

 

[C250JRH]

We used 2 x 20l Jerry Cans on the roof in 40 degree heat when we did the Mongol Rally 10 years ago. I looked at the 2nd fuel tank option and it was too complicated (Fiat Panda with single point fuel injection).
I seem to remember we only used the jerry cans once in the 10k miles.

 

[mct_cars]

BMW E39's use a slave pump to transfer fuel between two sides of the same tank. I assume it sits both sides of something like the exhaust.

I know this because in 1997 my father and I broke down on the motorway on our way back from being hosted by BMW at the NEC in a 2 month old E39. The transfer pump broke and we "ran out" of fuel despite there being about 20 litres in the tank.

Apart from a Nikasil recall it was the only breakdown in 10 years!

 

[Bellow]

Bag tanks are cheap secondhand. One from a Formula Ford will hold 2.5 gallons and will be shaped for behind seat fitment. One behind each seat will add 5 gallons of capacity.

Make that approx 4 gallons each and at worst you can use them like jerry cans - disguised as fitted tanks...