Transferring fuel from sub-tank to main-tank without engine running

[peter_mcc Senior Member Find all posts View Profile Close peter_mcc]

I'm stuck in the Kimberley - the car just died (see thread here).

I think the main tank is empty but the sub-tank is not because the transfer filter was blocked.

I understand fuel is drawn from the sub-tank to the main tank using the venturi effect from the fuel returning from the motor. Problem is... I can't get the motor running without fuel and I can't transfer the fuel without the motor running.

Any ideas on how to move the fuel from the sub-tank to the main tank? I'm in the bush so am a bit limited in what I have with me. I don't have any extra fuel - it's all in the tanks.

I have two x 20l jerry-can. I believe I can drain fuel from the sub-tank using a drain plug - problem is I don't know how to get it back into the main tank. Looking underneath at the filler pipe it seems that fuel "prefers" to go to the sub-tank first until it fills up then it goes into the main tank. Any ideas on how to fill up the main tank first?

I have an air compressor - could I blow air into a pipe to force the fuel to transfer? If so, which pipe?

Any suggestions are welcome. I'd rather drive out of here than go out on a truck (especially because there are 5 of us and a camper trailer which means we don't really fit in the truck...)

[Guest Close Guest]

You can disconnect the fuel filler hose to the main tank and get the fuel in from there.

[peter_mcc Senior Member Find all posts View Profile Close peter_mcc]

I've just removed the sub-tank stone guard and can see how to do that.

I'm a bit stumped on how to get the fuel out of the sub-tank - my Nov 14 build 150 doesn't have a drain plug in the sub tank. At the moment the best way I can see is to remove the fuel filler hose from the sub tank, syphon it into a bowl, tip it into a jerry can then tip it back in with the sub-tank filler pipe blocked.

Or perhaps my best bet is to beg fuel from people passing by - another 20l would probably completely fill the sub tank and start on the main tank, giving me enough to get the engine started and the venturi effect working.

[gspy4u Senior Member Find all posts View Profile Close gspy4u]

FOR DIESEL ONLY
bit of a emergency bush fix but if you have fuel in a jerry can you could always just run a hose from the can to the inlet side of your fuel filter. Leave the can in the engine bay, prime the fuel filter and hopefully the fuel pump should be able to suck it out of the can as you go (slowly) to where ever you need to get.
However, even if the venturi is not working, as long as you can get enough fuel it will fill the rear tank and then once full it will albeit slowly go into the main tank. It will froth and bubble and take ages but it will go in. Had ours fail on holidays and although it would sometimes take 30min's to fill as long as we kept filling up we could keep going.
If petrol then thats a hole different problem.

Otherwise if you have no fuel, and no drain hole in rear tank you could always just undo it and drop that tank. Only a few bolts holding it, drain the fuel from that into jerry cans, clog the filler pipe to that tank and fill up the main one. Just throwing out ideas. Good luck.

[peter_mcc Senior Member Find all posts View Profile Close peter_mcc]

We're running again! I ended up flagging down passing cars (luckily the Mitchell Falls Rd is fairly busy - good for help, bad for dust...) and buying 20l of diesel. I figured with the 20l I'd put in earlier and the fuel already in the sub-tank that would probably spill over to the main tank.

Lots of priming and a jump start from another passing car and it kicked into life. I left it running for 20mins - seems ok. Now I have to put everything back together!

If it's an option then I think that is the easiest way to get going - keep flagging down passing cars until you have bought/scrounged enough from jerry cans to get enough fuel into the main tank to get running again.

One trick - If you are filling the car from a jerry can I think the fuel will mostly go into the sub tank first. If you look underneath the car you can see there is a "T" in the filler pipe with the straight ahead bit going to the main tank and the T going to the sub tank. With a servo pump there is lots of volume/liquid speed so the fuel goes straight ahead. When you use a jerry can the fuel is going in a lot slower and so I think it will go into the sub-tank first. Once the sub-tank fills up then it starts filling the main tank.

Looking at it I think it may be possible to put a piece of hose (eg drinking water hose) down the filler pipe to get the fuel to go into the main tank first (ie so the end of the hose is past the "T" to the sub tank). I didn't need to try this but it looked to be one solution once you had diesel out.

If you take off the stone guard for the sub-tank you can see the pipes more clearly. It looked like it would be possible to remove the rubber filler pipe from the sub-tank and siphon the fuel out into a bucket/jerry can so it could be put back to the main tank. If you have this connection off you could try blocking it like gspy4u suggested, forcing the fuel into the main tank. It would work but you'd probably end up with diesel all over you if you're doing it on the side of the road - no matter which end of the pipe you block it is going to hold some diesel (50ml top end, 500ml bottom end) that would come out when you unblocked it.

[404pug Avid PP Poster! Find all posts View Profile Close 404pug]

Well done Peter! I have now printed off those 2 pages and they are in the car. Maybe any outback tourers should do the same. I assume the main tank is the one under the car and the sub tank is the one at the back?

[peter_mcc Senior Member Find all posts View Profile Close peter_mcc]

I assume the main tank is the one under the car and the sub tank is the one at the back?

That's what I'm calling them - I think that's how everyone else refers to them as well.