Auxiliary fuel tank.

I’ve got a number of Enmach tanks, and find them to be very good. Have an 80L water tank under the tray that has survived for over 5 years, and many kms over rough roads. Also have a 90L upright diesel tank that has about same footprint as 4 jerrycans.

Enmach has an eBay store too, called Ballistic4x4. Good, prompt service!

Bob

you don't say much but when you do it makes me giggle :)))

Allan - Good luck with trying to refill that 200L drum in any service station!

Cheers, Ron.

Just to clarify, Nick: I don’t even have a Ute yet :) I still have my Prado 120 but am ruminating over a nice, shiny new toy. The Prado has a factory 180 liter tank, which I have got comfortably used to. A good few years ago, I had a Defender 130 Ute with an auxiliary tank built into the aluminium canopy, which gravity fed into the main tank via a manual lever. It did mean I had to stretch my legs and flick a switch, which I never found an inconvenience at all. I think the original tank was 75L and the top up was 50 or 55L. Once I was comfortable with the main tank being low enough to accommodate the 50 L top up, I’d hop out and flick the switch... then carry on driving while it dribbled through. Very basic (You get used to “basic” in a Defender) ;) but worked really well. It was fitted directly above the main tank. I have heard some of these fancy replacement tanks don’t sync with the fuel gauge, which was a problem I never had.

Haven’t even decided on which bloody ute yet. Lots of pros & cons.

"some modern vehicle like PX ranger makes this type thing " interesting " :(("

Yeah, Nick, tell me about it!!

The Ranger/BT50 tank breather system is a PITA for transferring fuel from the auxiliary to the main. The issue is the main tank breather only allows air in as the fuel level drops during use. It has a check valve to prevent it breathing out (anti-pollution) and also to prevent fuel spill in the event of a roll-over.

There is a filler vent that is plumbed into the filler neck to allow air out when filling at the pump, but obviously that only works if the cap is off.

This means that to get gravity-fed fuel from the aux to the main reasonably quickly I have to remove the main filler cap to allow the main tank to breathe out as the fuel runs in. If I don't do that the transfer stops. I suppose if I left the filler cap on and drove, fuel would transfer at about the rate it is drawn from the main, but to do a bulk transfer I have to stop and remove the main filler cap. Time to boil the billy and have lunch, I suppose.

I did try splicing the aux breather (no fancy valves there) into the main filler breather so that the main was then open to atmosphere, but ended up with fuel leaks when the aux was full and the vehicle was parked not level or nose down. Fuel would run under gravity from the aux breather into the main filler breather and from there to the main tank and overfill it up the filler pipe and it would leak out of the main cap. As I said, PITA.

Cheers

Back in the 70’s, my in-laws did “half a Lap” in a Falcon station wagon.Melbourne to Perth, up the west coast, across the top and down the Stuart Highway. My F.I.L. had installed a 25 gallon fuel tank onto his roof rack. He fed this via a hose fitted with a ball valve through a modified filler cap into the main tank. Very agricultural, but did the job. Back then, the Eyre Highway And the Stuart Highway were still mostly gravel.

Frank P
With your system still fully sealed AND the aux breather T'd into the main tank breather, when fuel is run or pumped from the aux into the main, the air in the main will go into the aux and the fuel in the aux will pass into the main. Isn't that an easy solution and no leaks possible? Nothing vented externally! Shouldn't be a PIA at all.

G'day RMD,

Yes, that was the plan and the transfer itself did work after a fashion. I say "after a fashion" because in part of the modified breather plumbing there was an unavoidable P trap that inevitably got fuel in it after filling the aux tank. The gravity feed could not provide enough pressure/vacuum to move the fuel in the P trap, so the transfer would stall. An electric transfer pump would have fixed that, but I didn't want the complexity.

But the main issue in that set-up was as I said above - if the aux tank was full and the vehicle was not level or tail down, fuel would run from aux through the modified breather plumbing to the main and over fill it to the point where it would leak past the main filler cap.

I have changed the breathers back to standard and no more problems other than I have to plan my fuel transfers a bit.

My system is that it gravity feeds from 2nd tank into the breather on the main tank filler pipe( that's the breather from the tank when refilling at the servo) with a stop tap .. works ok BUT you must be stop /turned off as if you were filling up in s/s . if not fuel gauge will stay the same I.E doesn't recognise extra fuel in the tank , till it comes back to where it was before you started transfering the fuel ..Bazar .. also little hard to refill at service station aswel ...airlock .

I had a steel aux fuel, made by Don Spears in The Alice, fitted to our '82 Hilux d/c, using the gravity feed method. Fitted between the wheel wells, I hadn't allowed for a tap of any sort(chasing max capacity, which was about 80L) so the tap used sat outside in the wheel well.

Initially, I would use about 75% of main tank, then turn on the aux & it would siphon slowly into the main. Later on, I found that the tap could be turned earlier, & the syphoning effect would more or less keep time with the fuel usage.

The filler was mounted high up on the side of the Flexiglass canopy. Had filling problems, mainly because the breather pipe was only 8-10mm. In hindsight, the breather pipe/hose needs to be 20-25mm, to reduce airlocks & improve filling time.

Bob

Bob Y: Don ? spears (Spears sheet metal ?)
I think you may mean either Dallas or Jack depending on when you had that made. Have had a few Brown Lemonades with them boys back in the day :))
Good Tradies..

NickB I have a gravity feed setup like yours on my Landcruiser and my gauge still moves whilst driving........it is a nice feeling driving along chewing up the miles and watching your fuel going slowly up instead of down :)

Nick,

Talking mid-80's, re that tank. Don would have been their dad/uncle?

Think Spears used to make those "Territory Bars" too?



Bob

BobY : maybe uncle ??
Yes they made those bull bars under licence of some sort .
I think the designer was a station person maybe named (lally ??) started back in the 47 series cruises utes .
Back in those days there was no ARB /TJM like there is these days. we would make tanks and bars to suit customers requirements..

Ive seen one bloke at landor racecourse do this on his 150 series prado. dry break hoses the works just had to suck the diesel down the line test a sample in mouth then attach modified filler cap into main fill point. commented he even driven past WAPOL with line attached and they didn't turn a eyelid

The downside is all the boat tanks are petrol based not designed for diesel. what reason for this is I have no idea, maybe diesel causes material to deteriorate quicker than petrol based fuel.

I considered it for my own prado but 1 tank up at height is limit of the off road roof load on prado 120 series

Dean.
There are many boats which are diesel powered so diesel boat tanks should be commonplace. Also, the material in a yellow or red tank is the same poly , just different colour for ID. My diesel tank is red, ie, petrol intended. Just happened to be what was available for the price at the time.

This is the kind of tank i was thinking of
https://www.whitworths.com.au/sailmaster-stainless-steel-cruisetank-60l

In a Austin 1800 ? I reckon he was pushing his luck with that weight on it's roof, were not known for their strength.

I hear what you say, but there you go. :)
He was a builder who lived in Darwin and regularly commuted between there and Adelaide loaded like that. It was a DIY pack rack.
And of course it was still unsurfaced between Port Augusta and Alice and about 1/3rd of the WW2 bitumen between Alice and Darwin had reverted back to gravel.

The pack rack on the Mini was a DIY roof top tent. We chose to only carry 2 spare wheels up there. The rear seats had been removed and the jerry of fuel was in the boot and everything else was inside the car.
Cheers,
Peter
OKA196 motorhome

Rack on your Mini appears to have 6 legs, the Austin has only 4, I would have thought with that weight it would have torn the gutters off it. I tore the gutters off a FJ40 carrying one spare wheel, two gerries, and a tin tool box with about 50kg of tools and it had 6 legs and a rail that ran the full length of the gutters but was continually on rough unmade roads, not saying that "Highway" between Adelaide and Darwin was any better in places.

The Austin rack was 1/2"water pipe from memory and may also have had full length rais in the gutter, but I can't recall now, it was some time back. :)

"....not saying that "Highway" between Adelaide and Darwin was any better in places."

Cheers,
Peter
OKA196 motorhome

Love it, the memories are still vivid.

Thanks Ron. I’ll look into the Brown -Davis jobs.

Good onya for refusing to cough up $50 ;)