Problems with aux fuel tank

purchased trusty old Cruiser with aux fuel tank , mechanic had to do a few repairs on it including directing the air line from the aux tank back into the standard tank ( not sure why but thats what was done )
The problem is trying to fill both tanks or i should say either tank but mainly the aux .
I think what is happening is that because both fuel inlet throats are very close together fuel is also going into the standard tank which is making it hard for the air to escape from t aux tank therfore causing the bowser to keep shutting off . Painfully slow and embarressing for me but also not wanting to vex the poor bloke waiting behind me to fill his/her vehicle .
Is there somewhere i could obtain a twin inlet gadget to eliminate this problem please ??

PS Hope i have explained myself clearly here ?!
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Reply By: Brian - Monday, May 26, 2014 at 23:30

Monday, May 26, 2014 at 23:30
Must add too that i am currently doing a house sit near Port Augusta so if anyone knows an expert with mods to aux fuel in SA ??!!
AnswerID: 533213

Reply By: Wayne's 60 - Monday, May 26, 2014 at 23:55

Monday, May 26, 2014 at 23:55
Hi Brian,

While you are enjoying your house sit, please send more information about your vehicle.
This is so we mere plebs cans try to give sound information on you query.
Standard tanks or AM fittings would help.
Yehicle model and year, would be a BIG help.

With that, we will see where we go....................

Wayne & Sally.
AnswerID: 533215

Follow Up By: Brian - Tuesday, May 27, 2014 at 10:39

Tuesday, May 27, 2014 at 10:39
Thanks for your queries Wayne , its a Toyota LCruiser hj60 with the 12HT motor , think the biggest problem is the aux tank has been DIY job , no serial no or make ! So am rather lacking in details what i can tell you ! I sort of know what the problem is or why its happening , its more a remedy or a part i am seeking . Have just been told that there is a firm in NSW maybe called Out Of Town who supply parts for aux tanks which have problems . Thanks again Wayne
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Follow Up By: Bob Y. - Qld - Tuesday, May 27, 2014 at 21:26

Tuesday, May 27, 2014 at 21:26

Out of Town used to be just west of Newcastle, and they build the Long Ranger line of tanks.

Had a HJ60 some years back and put an aux tank on it. Can't remember what brand it was, but it was supplied with a twin filler fitting that replaced the original Toyota filler. The main filler was standard size, but the aux was probably only about 11/4", so took a little longer to fill. These 2 inlets were taken off from a small box, that allowed you fill either tank, or with care, both tanks at once.

As mentioned above, you have to make sure that there are no kinks in any hoses, and that the filler hoses go as direct as possible to the tanks. Breather hoses at least 1/2" seem to work the best too, as per Toyota HDJ78/79's. Some of the later model tanks appear to have an air chamber designed into the upper surface of the tank, which I imagine, may reduce the effect of fuel splurge?


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Reply By: phasar - Tuesday, May 27, 2014 at 01:34

Tuesday, May 27, 2014 at 01:34
G'day Brian

I too had this problem on my Mazda BT 50.
It's a bit hard to explain, but I will try.
In my case a vent line ran from auxiliary tank to main tank,
unfortunately this line was too long and dipped below the main tank.
Auxiliary tank is above main tank.
While driving fuel was spilled into vent line and because of it's position
it stayed there.
This line no longer acted as a vent and consequently it took forever and a day
to fill auxiliary tank.
After much frustration, when filling, I ran a separate hose from the filler into the aux. tank which then became the air vent.
This fixed the problem but I could not work out what was wrong.
Took car to garage in Alice Springs and on inspection fault was corrected.
Vent line was shortened and fuel was no longer able to stay in line.

I hope this makes sense,if not let me know and I'll try to clarify.
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Follow Up By: Brian - Tuesday, May 27, 2014 at 10:59

Tuesday, May 27, 2014 at 10:59
Thanks for your reply Phasar, yeah i do understand what you are explaining , i dont think thats the problem with it but it could be ! Its worth checking out though . local mechanic suggested i run a vent line from the aux tank up through the body cavity and end it near a vent there but sure as eggs it would fume the vehicle out .
Changing tack here slightly a lot of travellers say why bother with a aux tank ,buts its not only the high cost of fuel but also the convenience of just being able to drive on , providing you are alert etc !
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Reply By: Member - mechpete - Tuesday, May 27, 2014 at 10:36

Tuesday, May 27, 2014 at 10:36
why on gods earth would you vent one tank into the other ,
never heard of it before , run the vent pipe from each tank up to the top an just below the cap on the filler neck ,works every time
mechpete .
AnswerID: 533235

Follow Up By: phasar - Tuesday, May 27, 2014 at 10:46

Tuesday, May 27, 2014 at 10:46

I think that's the way it is fitted, not a very good write up by me.
The problem is that if the vent line sags below fuel tank it gets fuel
into it and cannot then expel air.

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Reply By: Ross M - Tuesday, May 27, 2014 at 11:01

Tuesday, May 27, 2014 at 11:01
The vent from the aux should be "Teed" into the hose which goes to near the highest point on the filler neck.
Around 8mm hose from memory.

That hose allows the main to vent and will also allow the aux to vent unless the neck is totally full of fuel, then it bubbles and blurts back if neck too full.
Next to the neck,

Because the two fillers are next to each other you should be able to direct the nozzle flow into the aux or the main, at will.

Next to the filler neck but forward slightly is a tank vent collector with around 5 hoses connected to it. it is black ribbed plastic, but sorts the vents lines from the main tank so air can escape to that top 8mm line but return fuel to the tank..
Possible any of your aux tank, additional vents, should be plumbed with a t's into a couple of those lines too.
That should make it all breathe correctly with minumal blowback and airlocks.Well no more than usual anyway.

I always used to rock the vehicle when near full to get the air to find it's way to the top 8mm line which vents high in the neck.

PS You have to remove the rhs inner trim to get to the vents system. It will all look like a tin of thick black worms with additional lines connected.
AnswerID: 533237

Reply By: HKB Electronics - Tuesday, May 27, 2014 at 12:40

Tuesday, May 27, 2014 at 12:40
Brain if you have a later model cruiser the problem might be the same as those experienced by some Prado owners.

On the Prados there is a flap located in the fuel filler pipe at the inlet to one of the
tanks from memory.

The purpose of the flap is to direct fuel into the aux first I think so that it fills first, the reason being the breather pipe goes from the aux to the main and if the main fills first you can't get fuel into the aux as it keeps spitting back due to the fuel in the main tank blocking the aux tanks breather.

This is a common problem and removing the fuel filler hose at the tank and fishing around with a bit of wire generally frees the flap and cures the problem.

I would suggest you visit pradopoint and do some searching on fuel filling issues.


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Follow Up By: Brian - Wednesday, May 28, 2014 at 13:32

Wednesday, May 28, 2014 at 13:32
thanks HKB , no 'She ' is a golden oldie , HJ60/1
And thanks to everyone else who have tried to help and as i've said before , great site , great people , might even join as a member after being an onlookerfor a few years now !!
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